My Chinese Pistache tree has brown tipped leaves. What is the solution? Top

It is hard to diagnose this without seeing the tree or at least a picture of the tree. In our opinion, there could be various reasons for the brown tipped leaves. If it is a newly planted tree, the answer could be that it has gotten too dry; even an established tree can suffer in dry times. Over fertilization, weed killers or a chemical spill (even a small one) can also cause the brown tipped leaves.

This is a quality tree and worth trying to save it, if possible.
(Courtney Blevins, CF, CA and Parker County Master Gardener)

For any of the above problems, my best recommendation is to replace any grass with mulch under the tree and water it well during the dry spell.

Courtney Blevins, CF, CA
Regional Urban Forester
Texas Forest Service, Ft. Worth
www.ctufc.org

Please give me the relationship between broccoli, cauliflower, collard and kale. Top

COLE CROPS

The terms "cold" and "cole" sound the same but have different meanings. "Cold" of course refers to temperature. "Cole" refers to any of various plants belonging to the Cruciferae or mustard family. Even though you might not be familiar with the impressive scientific name or enjoy eating mustard you are certainly familiar with other members of this family, which furnish Texas gardeners with many gourmet delights during the winter months.

The mustard family includes cool season crops such as Brussels sprout, cabbage, cauliflower, collards, kale, kohlrabi, mustard, broccoli, turnips and watercress. All of these familiar garden crops can trace their history to a common ancestry of wild cabbage originating in the Mediterranean and Asia Minor area. The close kinship of these crops enables diversified usage of plant parts. For instance, Brussels sprout plants are grown by most gardeners for a miniature heads (sprouts) that develop in the axils of the leaves. However, the leaves of Brussels sprouts are considered by some to be milder and sweeter than those of the collard, which is especially grown for leaf production. Most gardeners are familiar with the fact turnips can be grown for the greens (leaves) or for the turnip roots. In other words, when growing a member of the Cruciferae family the saying "what you see is what you get (to eat)" truly applies!

This group of cole crops enjoy cool seasons and are somewhat cold tolerant. Cabbage for instance can withstand frost down to 20 degrees or even 15 degrees F. Cauliflower and chard are more sensitive to cold than broccoli, collards, kale, kohlrabi, or mustard. The conditioning of the plants as influenced by weather conditions prior to exposure to cold temperatures determine plant survival. Maturity of the plant also has much to do with the amount of cold that cole crops can survive. When broccoli plants have produced buds, even a light frost may cause considerable damage since clusters freeze, turn brown and ultimately rot.

The cole crops grow best at a monthly mean temperature of 60 to 70 degrees F. This occurs when temperatures are 80 degrees F. or less during the day and 60 degrees F. or less during the night. In most parts of Texas these ranges occur in October- November. In order to produce the best quality of the slower maturing cole crops, Brussels sprouts, cabbage, cauliflower and broccoli should be planted in gardens in August or early September. These crops can be directly seeded or transplanted into the garden area. Faster maturing cole crops such as collards, kale, kohlrabi, mustard, and turnips can be directly seeded into the garden as late as September. Of course, when you plant depends on where you live.

When you plant cole crops in the garden you are investing in a healthful life. Gardeners are in the business of producing health foods even though they may not know it. Vegetables contain essential elements for health and the enjoyment of eating fresh garden vegetables makes health fun. Exactly how necessary are vegetables to the healthy body? Some animals can synthesize vitamin C, but man, apes, birds, and a few other animal species lack this ability. Vitamin C cannot be stored in the body, making a daily supply essential to good health.
Cabbage, broccoli, collards, and other vegetables of the cabbage family are rich in vitamin C, as are leafy vegetables such as kale and turnip greens supply carotene, which the human digestive system converts to Vitamin A.

Proteins are nitrogenous compounds that are composed of amino acids. All vegetables provide some protein. The percentage protein in vegetable legumes is as high or higher than that of meat. Even non-legume vegetables such as sweet corn, Brussels sprouts, collards, and kale contain more protein than milk.
 

We have an outside deck with many cockroaches under it. What can we use to get rid of them? Top

The following are answers from several Parker County Master Gardeners.

1. Boric acid and anything that will draw them in like sugar

2. My thoughts on this:  boric acid and powdered sugar mixed together and placed in crawl spaces and around doors etc. I saw it in the paper several years ago. Sugar attracts them, boric acid kills them.

3. This is from the University of Florida "Dusts”:  Indoors, non-organic dusts, such as silica gel and boric acid can be placed in out of the way cracks and crevices. Can be applied with a bulbous type duster under sinks, stoves, refrigerators, behind baseboards, in electrical outlets and in cabinet cracks. Silica gel is finely ground glass or sand that rubs the protective waxes off the cockroach cuticle resulting in dehydration. Cockroaches walking across the boric acid pick up the dust on the sticky cuticle. As they groom off the boric acid dust they ingest it into their stomach and it kills them

4. Take horse apples (these are the large rough, green apple-like fruit of the Bois d'Arc tree) in the fall and place them by outside doors and around the foundation of the home and the roaches won’t come in. Use whole apples, will need to be replaced each year. They don’t smell.

5. We just mix a little sugar with boric acid. We use it to also get rid of ants. A tablespoon of boric acid with about 1/2 teaspoon of sugar placed in a shallow container on the floor. We keep one in the RV.
Please try one of the above methods because they are affective and safe to use.

You can also treat with chemicals (find the large plastic containers with the tubing and sprayer attached). You can also call a professional exterminator to do the job but we recommend the above methods first. PLEASE!

My child is becoming interested in gardening. What are the first steps to encourage this interest? Top

My Very Own Garden
A garden design for children

Help your child plan and plant this miniature garden but let them be the primary gardener. Annual flowers are easiest to take care of and can be purchased inexpensively by the flat. Although seeds are the least expensive, it may be harder for kids to be patient.

PLAN:
Let your child design and plot the shape of their garden. A 4x4 foot rectangle is the easy to dig and small enough to maintain. A border garden works well, as long as your child can reach the back row. If you already have an existing garden, you could give your child a corner or raised bed of their very own. The circular plan (below) is five feet in diameter with a one foot bisecting path. This makes weeding and cutting easier.

Draw their ideas together on a piece of paper. Do not over plan their garden with graph paper, etc. It is recommend you help them plan which flowers to plant. Does your child want a fragrant garden? A garden for cutting flowers? A garden to attract butterflies? Would they like to combine flowers with vegetables?

Low maintenance flowers like petunia, pansy, marigold, alyssum, snapdragon, daisy and cosmos are a great start. A garden book with color pictures will be a big help.

Then a trip to the nursery is in order. After your plants are purchased it is time to dig, turn the soil and plant. Most kids need help with the spacing and watering the first time. Kids may tend to over feed and water their new gardens so help them with a schedule for watering and feeding. After a while you will need to give a lesson on weeds. Many weeds are flowering and pretty, but will choke a new plant. Pesticides are NOT recommended for children's gardens. Ask your local nursery for natural pest removal tips --Ladybugs remove aphids, rolled newspaper for earwigs etc.

Designing and Planting a Butterfly Garden with Kids

Acres of land are not necessary for a successful butterfly garden.
A window box, or container garden will do the job.

First, have your child select the plants from the list below.
Then, help them draw a simple plan, with proper flower spacing and plant accordingly. Use the steps below for planting your garden:

1. Dig the garden, break up the soil with a garden fork, add peat moss if necessary, creating a loose, fluffy soil for the young plants' tender roots.
2. Plant short flowers in the front and taller plants in the back. This design allows proper sunlight and keeps both low-feeding and high-feeding butterflies happy.
3. After planting soak the soil. This is good for the plants but also helps butterflies that suck the wet soil for salts and fluids--a behavior known as "puddling".
   If you are starting with seeds...do NOT soak the soil but follow the instructions on your seed packets.

Tip: Planting groups of flowers rather than single plants will attract more butterflies. Keep your butterfly garden pesticide-free!

Plants that Attract Butterflies

Annuals
Coneflowers, impatiens, marigolds, phlox, sunflower, verbena, zinnia, cosmos

Perennials
Asters, bee balm, butterfly weed, chrysanthemums, daisies, coneflower, sedum, aster, daisies and yarrow

Planting parsley to attract caterpillars will help to generate a very active butterfly garden.

For more information on butterfly gardening refer to Parker County Garden Tips on this website (July 2007).

Are red tip photinias the same as Fraser’s Photinias? Top

Yes, these are one and the same. (See the question/answer on red tip photinia diseases in this FAQ). A related species is Photinia serrulata (Chinese photinia) a coarser texture, taller plant (12 to 20 feet). It makes an excellent screen and is resistant to heat and drought but is highly susceptible to powdery mildew, during moist spring weather. This plant can be seen in old landscapes with its brick-red fruit in winter but is rarely seen in nurseries or newer landscapes. It is a quality plant, unlike its relative Fraser’s red tip, and should be considered in modern landscapes.
 

Can red yucca be transplanted and if so, when? Top

Several Master Gardeners replied to this question.  Here are their responses.

Is there value in whitewashing tree trunks? Top

"I cannot see any value in this practice."
   Special thanks to Courtney Blevins, CF
   Regional Urban Forester
   Texas Forest Service, Ft. Worth

"I do not think it is of any value. I think it was done in the past to make the trees more appealing."
   Special thanks to Dr Jerral Johnson, Professor Emeritus
   Dept Plant Pathology and Microbiology, Texas A&M University

What is the plural of Cactus; Cactuses or Cacti? Top

Actual, either is correct.  Check here for the definition.

How to prune salvias? Top

You may not want to bother removing the flower-bearing stems on many types of salvia that are grown for hummingbirds. These stems simply dry up by themselves and since our annual salvias generally do not produce seeds in great number; this need not be a concern for you. Salvia coccinea does produce seeds on these stems. Some gardeners recommend that flower stems should be removed from plants once the flowers stop looking attractive in order to prevent the plants from producing seeds, which can reduce future blooming. This does not happen with salvia coccinea, which produces both lots of seed and lots of flowers all year long. Once any part of a plant turns brown and brittle it may be removed without harming the plant, since brown and brittle indicates a dead part of the plant.

If you want to promote branching in salvias, you can cut off the tip of each stem, which will usually result in two new stem tips being produced from the axils of the last pair of leaves left on the plant. When growing fall blooming salvias you can cut or pinch back the stem tips regularly until about the end of June, then stop cutting to allow the plants to produce flowers. It is necessary to remove only the growing tip of the stem to encourage branching, try to cut back after a few inches of growth has occurred to encourage the maximum number of branches. Try not to remove more than an inch or so of the stem, but if your salvias have gotten too tall you might remove much more than an inch to prevent them from becoming weak-stemmed and falling. This type of cutting back is good for salvia elegans, s. mexicama, s. iodantha, s. madrensis, s. involucrata, s. puberula, s. slendens 'van houtte', s. leucantha, s. purpurea, s. gesneriflorae, and perhaps other varieties. Cutting back isn't usually necessary for salvias that bloom all summer, because cutting back would delay flowering. Once salvias flower, they generally branch out below the old flower stem automatically, so a species like s. guaranitica doesn’t need to be cut back. Some like to tidy their salvias and clip off the spent flowers, this is your choice but not really necessary.

Each salvia variety can have its own set of pruning instructions. Some need hand pruning to each stem, while others can just be clipped-off, and still others can be sheared. Learning from experience what is best for your salvia varieties is sometimes the best way to achieve the look you want. Gardening is an art of trial and error or trial and success.

General rules can apply to pruning salvias:

Woody stems are pruned down to the lower set of new leaves -- ex. greggii.  Softer, brittle stems are pruned to the ground (or new growth if it's started already) -- ex. leucantha

Where the leaves are basal (low to the ground in a circle) you only clean away dead leaves and remove any old stems.

Shrubby, but not woody salvias are pruned rather short -- down to lower new leaves -- ex. microphillia, involucrata, elegans, "Black & Blue.”

Note from a PCMG member: I have Black & Blue salvia guaranitica and where I have it, it must be very happy because I have to prune it hard a couple of times during the summer just so we can walk by it. I usually cut the spent blooms away to keep it flowering all season. It grows so vigorously that I have to dig some of the roots up every year just to keep it confined.

My Victoria blue salvia is beautiful what about pruning or taking cuttings from it?

Wait until you see new growth. Use the “asparagus” rule to trim salvias. Bending the stem until it snaps (towards the outer end) will reveal the approximate area where the transition of the woody growth to new green growth is. This is also the point where cuttings are taken.

Treat shrubby woody-stemmed sages like greggii and microphyllas that form twiggy, woody growth like roses. Definitely do not cut these to the ground.

Cutting to the ground is only good for those salvias that form short stolons underground and send up new shoots, like leucantha, some microphyllas, guaranitica, and others. If the plant was rooted and set into the ground with no nodes beneath the soil line, it will not send up shoots in any case. You can often tell this has happened when there is a thick trunk coming from the soil, and the first node has a multitude of stems coming from it. Cut that off, and you have a dead plant.

Questions about cutting back salvia greggii:

Re-blooming salvias, such as salvia greggii should be pruned back periodically during the summer. To make the job easier, use hedging shears, and remove only the spent flowers and a few inches of stem below.

Note from Parker Master Gardener: In Parker County, salvia greggii needs to be cut back to look better, mine gets rangy looking and the wood gets brittle and does not bloom as well.  Plus pruning in February will make it thicker and healthier looking in the spring.  I suppose you could just leave the salvia greggii alone but mine does better cut back by one third every February. 

When do you prune fall blooming salvias? Top

Fall-blooming salvias such as leucantha should be pruned during the summer to keep them compact, reducing the need for staking. To make the job easier, use hedging shears, and remove only the spent flowers and a few inches of stem below. Any of this type of pruning should be completed prior to September 1, since flower buds begin forming about that time.

Note from Parker County Master Gardener: As for the leucantha, it has to be cut back completely to ground as does Victoria blue salvia because it dies to ground. 

Where to cut nemerosa? Top

Note from Parker County Master Gardener: I have nemerosa blue salvia 'May Night' meadow sage and they need deadheading/pruning.
 
After the flowers of nemerosa fade and seeds begin to mature, you should prune stems to two active leaf nodes to encourage branching and repeat blooming. Plants may be pruned to crown before winter comes, and if temperatures fall to the teens or below, protect them with mulch.

How can I control spider mite on Junipers? Top

Spider Mite: Mites are not insects but are more closely related to spiders are serious pests of juniper. They are very small and not seen easily with the naked eye. They have piercing mouthparts that they use to suck plant sap. Their feeding results in speckling (formation of tiny yellow spots) on needles. Some needles may turn brown and drop off. With heavy infestations, fine webbing may be seen on the plant. Several seasons of heavy mite feeding may kill a juniper. Although most spider mites increase in numbers during hot, dry weather, spruce spider mites are cool-weather mites. Their population peaks during spring and fall, but drop dramatically during the heat of summer when predators feed on them.

Control: Naturally occurring enemies of mites include various predator mites, ladybird beetles (ladybugs) and other insects. These predators will usually suppress mite populations. Since insecticide use kills beneficial predators as well as mites, insecticides should be avoided unless absolutely necessary. Misuse of insecticides can result in increased problems with mites by causing the death of natural predators of the mite. Miticides, labeled specifically for mite control, are less harmful to beneficial insects. Mites can be removed with a strong spray of water, if applied on a regular basis.

To determine whether insecticide use is needed, it helps to know how many mites are present. Hold a white sheet of paper under a branch and strike the branch. The mites that are knocked off will be seen crawling around on the paper. If dozens of mites are seen per whack, serious damage can result. Continue to check population numbers at seven to ten day intervals. Pesticides labeled for homeowner use against spruce spider mite include insecticidal soaps, dimethoate (Cygon 2EC), acephate + hexakis (Isotox Insect Killer Formula VI). As with any pesticide, read and follow all label directions and precautions before using.

NOTE: Control of diseases and insects on large trees is usually not feasible, since adequate coverage of the foliage with a pesticide cannot be achieved.

What is the Burford Holly origin? Top

The Burford holly was discovered in Atlanta, Georgia’s Westview Cemetery in the 1900’s. A member of the Chinese holly family, it is an evergreen shrub that has been a proven winner for over 100 years. In the fall, they are covered with long lasting large red berries. They are dependable for berry production because this cultivar does not need pollination to set fruit. Learn more about the Burford holly in The Real Dirt a Gardening Handbook for Parker County.

How and when do I fertilize newly planted Leyland Cypress? Top
Answer courtesy of:
Courtney Blevins, CF
Regional Urban Forester
Texas Forest Service, Ft Worth

First always have a soil test on the area before planting any tree. Newly planted and younger trees should probably not be fertilized at planting because it can damage new roots, unless soil test shows need. This is an issue that has yet to be resolved. Some research says fertilize new trees and some does not. Seems if you do so carefully though you will come out ahead Established trees in yards should not need extra feeding. They receive adequate fertilization as lawns are fertilized using a 4-1-2 or 3-1-2 ratio fertilizer. (Note from Master Gardener - I make an extra pass around the drip line of trees at the time I fertilize the lawn and this seems to be enough fertilizer). Any heavy feeding should be in late winter for spring and summer growth; no special summer or fall feeding. Do not apply high-nitrogen fertilizers until the tree has developed good root system that can support vigorous top growth.

What about lava rocks as crape myrtle mulch? Top

The problem with using a product like lava rock, as mulch is it is difficult to work around. Rarely can any plant be left alone and not eventually require attention and when this happens if you have to deal with lava rock, you may regret using that material. It also creates extra heat around plants and often does not look natural like tree bark, shredded leaves, hulls and other mulches that will break down. These products add nutrients to the soil when they breakdown and lava rock does not.

I need information on Horticulture/Dormant oil use in the landscape. Top
Taken from: Texas AgriLife Extension Service,
Texas A&M University, College Station, Texas
January-February 2004

Horticultural Oils
by Cynthia W. Mueller, College Station, TX

January-February is a good time to control scale insects on evergreen shrubs and trees such as camellias, hollies, bay laurel, myrtle, euonymus, citrus, photinias and boxwood through use of a horticultural oil spray. Fruit trees may be sprayed at this time of year in order to control insect eggs that may have been laid in bark and twig crevices.

Usually, the oil treatment will need to be applied only once a year, and is an excellent way to smother a pest that is difficult to eradicate. At times even live oaks fall prey to scale, but due to difficulties of size these plants are much harder to work with. Horticultural oils also have the benefit of being less environmentally harsh than pesticides.
Trees and shrubs are often unable to withstand the continual drain of sap from these sucking insects, and may ultimately be killed. Treatment consists of thoroughly spraying with horticultural oil according to directions, from every direction over the leaves and twigs.

There are several thousand species of "scale insects". Armored scale insects are capable of navigating to fresh feeding grounds when very small, but then live and feed under a protective hard, waxy shield as adults. Tea scales, oyster scales, euonymus scales and wax scales are examples of these. Control sprays work best at a time when the young, unprotected 'crawlers' are present on twigs and bark and can also aid in protection against aphids, white flies and spider mites.

Scales often secrete "honeydew", a sweet solution that is soon invaded by fungus, creating a darkened, sticky appearance on leaves and even on other nearby plants known as "sooty mold". After scale insects have been killed, the bodies will still stick in place and the blackened, sooty mold effect has to wear off the leaves over time.

Other species of scale present a more cottony appearance. Some, such as mealy bugs (Pseudococcidae), are able to move about on plants throughout their lives, and may be found down inside bulbs as well as in clusters over plants, or concealed in debris such as fallen leaves nearby.

For successful spraying, look for a period in the early spring that will be relatively warm, but without a forecast of rain for at least two days (45 - 70 degrees F). Carefully follow the label directions in order to apply the correct dilution formula, especially if you plan to spray fruit trees beginning to break dormancy. If there are any doubts, spray a small area and wait a few days to check the results.

After a few weeks, check to see if spraying has killed most of the scale present. Pry off a domed scale with a thumbnail and press. If the shell is dried, the treatment has worked. If there is still yellow, orange or white viscid material, the scales are still living.

Note: (This material appeared in the web periodical Horticulture Update, Drs. William C. Welch and Douglas F. Welsh, Editors, Department of Extension Horticulture, Texas A&M University, College Station, Texas)

What are those worms that hang from my trees in the spring and how should they be treated? Top

Cankerworms are a major defoliator of broad leaf trees in east and central Texas. Such outbreaks of cankerworms are not predictable and reach high levels with little warning. Cankerworms pose a threat to broad leaf trees. Early detection and control measures are necessary for proper control...read more

Is there something that can be sprayed on plants while they are dormant to rid them of insects before they do damage? Top

You can rid your defenseless trees and shrubs of inconspicuous killers by using a prophylactic spray. The spray that should be used is referred to and sold under many brand names as dormant oil, horticultural oil or scale emulsion. These are highly refined oils (not motor oils!) that spread uniformly on the bark of trees and shrubs to which it is applied and coat non-mobile, dormant insects on the tree smothering them to death. Heavier oils may have to be applied with a tank (pump-up) sprayer, which can apply the fully diluted product, rather than with a hose-end sprayer, which may become clogged. Applicators should frequently shake sprayers to agitate the water and chemicals mixed since plant damage can occur if a concentrated oil spray, caused by solution separation, is applied. Mix dormant oil at the recommended rate on the product label.

It is best to spray before buds begin to swell. If buds of trees and shrubs have begun to swell slightly, go ahead and spray. Although some of the buds may be damaged, the benefits of spraying dormant oil far outweigh the possible repercussions. Applying a dormant oil spray this late will also serve to cover pruning cuts and can serve as a second attack on stubborn pests which were not killed by an earlier oil application. The closer the application is made to budbreak, the greater the kill. Do not spray trees that are in full bloom.
Spraying of dormant oil should occur on a clear day when the temperatures are expected to remain over 50 degrees F. for at least twenty-four hours. The ideal temperature for application is between 40 and 70 degrees F. in order to get the oil to spread out over the tree and cover all crooks and crevices. Try to avoid applying dormant oil when severe freezing trends are expected in the 3-4 days following application.

CAUTION: The use of a dormant oil mixture will not only kill, but also annihilate, annual flowers such as pansies, bluebonnets or snapdragons growing under or near plants to be treated. To avoid this, completely cover such tender vegetation BEFORE spraying nearby trees and vines with dormant oil.

Every year I try to grow tomatoes with little success. The undersides always turn flat and black. Top

Blossom end rot is a deficiency of calcium. The problem starts at the bottom of the tomato as a pale, brown spot that turns black and flattens the bottom of the fruit. A condition that seems to contribute to blossom end rot is irregular levels of moisture in the soil. Tomato plants take in nutrients, including calcium, through moisture. Inconsistent watering deprives them of these nutrients. Water regularly, every four to seven days is usually sufficient. During droughts or if you are gardening in containers you may need to water every day. To prevent leaf diseases, water low, keeping the foliage as dry as possible.

To keep the soil consistently moist, cover it with a two to three inch layer of mulch. Keep the mulch away from the stem of the plant. You'll find this also helps keep weeds down.

How do I get rid of bagworms? Top

The Ohio State University Extension Service has written this article on the control of bagworms.
Ohio State University Extension Fact Sheet
Entomology
Bagworm and Its Control
HYG-2149-90
by D.J. Shetlar

Please give me information on growing crape myrtles, especially diseases that effect them. Top

This article appeared in the May 2002 web issue of Horticulture Update, edited by Dr. William C. Welch, and produced by Extension Horticulture, Texas AgriLife Extension Service, The Texas A&M University System, College Station, Texas.

Crape Myrtle Care

By Dr. William C. Welch, Landscape Horticulturist
Texas A&M University, College Station, Texas

Summer in Texas would not be complete without the abundance of crape myrtle flowers now beginning to be conspicuous over most of the state. Proper fertilization and pruning usually result in a long display of flowers of three months or more.
Fertilizer recommendations are best made after reviewing soil test results, but a general recommendation of 2 pounds of nitrogen per 1,000 square feet of root area is sufficient for most trees and shrubs. This can be repeated again in the late fall. The first application should be made just before new growth begins in the spring. The number of square feet in the root area is determined by the branch spread of the tree.

The most significant disease affecting crape myrtle is powdery mildew. This can be controlled by spraying with Benomyl or Funginex, used according to label instructions. Mildew is usually less of a problem if plants are located in open sunny areas where air circulation is good.

Pruning is best done in late winter before new growth begins. The structure and trunks of crape myrtle are among their chief assets; therefore, pruning should normally involve only removing dead and twiggy growth to expose the sculptural character of the tree.

For dwarf varieties or in shrub borders where crape myrtles may be grown only for their blooms, severe pruning will help insure larger and more prolific flowers. The pruning of faded and seedy blossom heads will usually promote repeat blooming late in the summer.

For something different, try some of the dwarf type crape myrtles in tubs or pots on the terrace. They do best in sunny areas, and are as satisfactory for container use as they are in the ground.

What do I do about webworms? Top

http://citybugs.tamu.edu/IntheNews_Details.asp?ID_Key=435#
Date Published - 6/14/2007

Dallas, TX. Here's a riddle: When is silk ugly? And the answer doesn't have anything to Father's Day ties. Silk is ugly when it's webworm silk and it covers your favorite tree.

Many north Texas homeowners are noticing unsightly silken webs appearing on a variety of trees this summer. One of the most common foliage feeding caterpillars in north Texas is the fall webworm, Hyphantria cunea. Despite its name, the fall webworm is active throughout the warm season and will produce about three generations in Texas. The early appearance of fall webworm caterpillars in 2007 may indicate a banner year for this pest.

Fall webworm is a caterpillar, the immature stage of a non-descript white moth. The adult moths emerge from coccoons in early spring and lay their eggs on the undersides of leaves of preferred host plants. As soon as the young larvae hatch, they begin spinning a loose silk web that soon covers the tips of the branches on which they feed. Inside the webbing, dozens of hairy caterpillars will be found feeding on the leaves inside. Fall webworm caterpillars are variable in color but have a double row of black dots down their backs and grow to about one inch in length.

If you are sharp-eyed enough to catch fall webworm nests before they spread, you may be able to prune or knock the infestation out of the tree. Place a garbage bag under the web and use a rake to pull off the webbing and knock down the caterpillars. If you cannot reach the web, or there are too many to remove by hand, insecticide sprays can eliminate the infestation. Low impact pesticides for tree-feeding caterpillars include insecticide soap, horticultural oil, Bacillus thuringiensis, or spinosad insecticide sprays. Pyrethroid insecticides will also provide fast control of most caterpillars.

Unless infestations cover a tree, they are usually not that damaging to tree health. An otherwise healthy tree will withstand up to 40% defoliation during the summer months, and will often re-leaf after being stripped by caterpillars. So if you don't treat in time, don't worry. Chances are your tree will survive, although you may not be happy with its "webby" appearance.

Other common, summer-feeding tree caterpillars include the eastern tent caterpillar (makes webs in branch crotches and lives in the eastern half of Texas) and the genista caterpillar (commonly found on Texas mountain laurel). These caterpillars can be controlled in much the same way as the fall webworm.

Contact Information
Michael Merchant
m-merchant@tamu.edu

Is black mold on a bag of peat moss dangerous to breathe? Top

It is never a good thing to breathe black mold. If you find this before making your purchase, leave it alone and go to another bag. If you have already purchased the bag and for some reason you then find the mold, my advice would be to wear a mask over your mouth and nose while opening the bag and using it. If the contents were questionable, I would empty them into an area where children and pets do not play. I probably would put it into my compost pile because it heats up and should decay the contents along with the other materials in my compost container. I still would wear a mask when working with this bag but it is not a bad idea to work with a mask when using peat moss at anytime.

How do you kill vinca minor? Top

Round-up works. It may take a couple of applications to do it completely. For best results: mow or use a weed eater/wacker on the vinca. Water well for a week or so, getting it going well. Then spray, when the temperature is between 65-85 degrees. It takes longer to work if the temperature is much colder or hotter than that. I find that a few drops of regular dish washing soap (not dish washer soap) helps the Round-up stick to the glossy leaves of the vinca minor.

This treatment should be done on a day with no wind. Be careful when applying this treatment and do not get the Round-up on any desirable foliage.

Please give me the information I need to grow asparagus. Top

Asparagus is a highly productive vegetable best suited to cooler areas of North and West Texas. Grown for the stems or spears, a well tended planting yields 8 to 10 pounds or more per 100 square feet of bed or 24 to 30 pounds per 100 feet of row. Read more here...

http://www.pcmg-texas.org/asparagus.htm

How do I care for a Kalanchoe that was given to me as a gift? Top

Your Kalanchoe is a wonderful succulent (it can be put outside during warm weather but will not withstand cold temperatures). It makes a great houseplant, if given bright light such as from a southern window.

Keep it happy with a monthly feeding (from spring to fall) of a general-purpose liquid fertilizer. The spent blooms will fall off by themselves but you can encourage more flowers by removing them yourself. It will require a resting period after blooming. If you do not care when your Kalanchoe blooms, just leave it alone and it will bloom on its own. If you want it to bloom approximately the same time each year then you will need to regulate its environment. It will require about six weeks of shortened days (this means about fourteen hours of darkness). When the days are shorter, reduce watering and with the longer periods of darkness, you will soon have blooms again
Your Kalanchoe can be propagated by breaking off a small limb and placing it either in a small vase of water or in potting soil. If in soil, keep it relatively moist until roots appear. Pull on the limb and if you feel resistance that should be a sign that it is developing roots.

I have a Kalanchoe that was given to me in 1988 in a four-inch pot and it is large, beautiful and blooms at least two times a year. I have also given away many “starts” of this plant.

Information about Oak Wilt in Parker County Top

We have received many questions about Oak Wilt and the concern for our beautiful oak trees in Parker County. There is no better information on this subject than that found in this article from the Department of Plant Pathology and Microbiology at Texas A&M University:  Eight Step Program to Oak Wilt Management

I was told Red Tip Photinias are susceptible to disease. Should I pull them up and plant something else? Top

Fraser’s Red Tip Photinias are susceptible to a deadly disease called Entomosporium Fungal Leaf Spot that has also been found on Indian Hawthorn and Loquat. This is why red tip photinias are not being promoted for landscapes.

If you have photinias in your established landscape and they are healthy, you may want to leave them but if you see the maroon speckled leaves, you may want to consider removing the diseased shrubs. After the terrible winter in the early 80’s, wax leaf ligustrums froze to the ground and many of us turned to red tip photinias as replacements. They were over planted and the disease started to devastate this species. We had many of them in our landscape and some of them have since been removed because of the disease but we still have ten that are beautiful and the size of small trees. I cannot tell you why some died and some have survived and flourished that is just the way it is in nature.

Gardeners are sometimes concerned when a plant develops a disease that it will spread throughout their garden. Most diseases are species specific and will not bother another type of plant even when they are planted in the same area.

So my recommendation to you is to evaluate your photinias in your landscape and if you like them and they are healthy, enjoy them.

What is the best grass for shaded areas in Parker County? Top

We do not have a perfect grass for heavily shaded areas and sometimes have to go to groundcovers to cover these areas. If the area is lightly shaded, you will have some success with St. Augustinegrass but it still needs at least four hours to survive and six hours to really flourish. Bermudagrasses need full sun and will not tolerate shade. Buffalograss must have full sun. Zoysia needs six to eight hours of sun to flourish. Tall Fescue has good shade tolerance but is a cool season grass and has little tolerance of our hot, dry summers.

I think St. Augustinegrass is still the best for lightly shaded areas and sometimes you can trim up limbs on trees or shrubs to allow more sun to get to the grass. Be careful when you do this and be sure you are not destroying the look of the landscape by poor choices in trimming. You may decide that groundcovers or hardscapes are the answer to your shaded areas. They can be quite beautiful and add interest to your landscape.

You will find more information about lawn grasses and ornamental grasses in the real dirt A Gardening Handbook for Parker County.

What are the recommended vegetable varieties and planting dates for Parker County? Top

This article can be used for Parker County and shows the recommended varieties and the planting dates. For further information on vegetables for Parker County, refer to the real dirt A Gardening Handbook for Parker County.

What do you do about leaf-rollers on Cannas, Vinca Minor and Vinca Major? Top
Researched by Parker County Master Gardener La Donna Stockstill

Systemic insecticides are a special group of insecticides that are taken up into the plant through its leaves or through its roots. Unlike most insecticides that remain on the foliage, systemic insecticides make the plant sap poisonous to feeding insects.

Damaged canna blades become notched and ragged. When they mature and open, they look like someone has shot them with a B B gun. One finds robust caterpillars hidden inside leaf rolls. Canna leaf-roller caterpillars are clear white at first. They become semi-pale green with age. Lesser canna leaf-roller caterpillars are smaller and yellow. Large ornate butterflies lay eggs from which they hatch. The caterpillars spin silk thread used to pull leaf edges together. They hide inside the protective tube, presumably to avoid predators.

Leaf rollers in late summer are devastating to foliage of vinca major and to some lesser degree to vinca minor and should be prevented with systemic insecticide before they begin. Apply a systemic insecticide 2 to 3 weeks before you traditionally would see their damage start to occur. If the damage has been done, you will may want to cut the marred foliage back and allow new growth to cover the area.

Control canna, vinca minor and vinca major leaf rollers with BT insecticides, Orthene or Sevin. BT insecticides contain a bacterium (Bacillus thuringiensis). They are sold under trade names such as Dipel. Caterpillars ingest the bacterium and die shortly thereafter. Orthene and Sevin are chemicals that may give a quicker kill of established populations. BT-type insecticides have worked.

Information needed about Penstemon cobaea. Top
Researched by Parker County Master Gardener La Donna Stockstill

Texas with its varied soil types and weather conditions has 22 species of this wildflower. Like many Texas native wildflowers, penstemons transcend their native habitats and thrive in many locations. Many penstemon species and varieties prefer well-drained soils and full-sun exposure. Many varieties are evergreen and while most bloom in the spring, there are some that flower during the summer months.

These perennials thrive in clay-based or rocky soils and require no soil amendments or fertilizers to bloom year after year but really all perennials can benefit from well-seasoned compost worked into their planting beds and penstemons are no exception. Most penstemons grow in alkaline soils; therefore they do well in Parker County. It is good to know your soil pH because this can determine the varieties of penstemon you can grow for the greatest success.

penstemons have trumpet-like blooms arranged on multiple flower spikes and colors range from blue to white and many shades of purple and pink. Some to look for are Penstemon cobaea, commonly called prairie foxglove; P. triflorus, known as Hill Country penstemon; and P. baccharifloius, commonly known as rock penstemon.

Prairie foxglove is native to our area and in spring it produces large, bells of white, pink or lavender and is a real standout in the landscape. Prairie foxglove is an evergreen perennial and its fuzzy foliage is welcomed to the winter garden. It prefers sunny locations but will tolerate some afternoon shade. Hill Country penstemon is evergreen but its blooms are smaller and are a rich, dark pink. Both can be grown from seed and plants will produce plenty seeds if left to mature, which usually takes about three months. If planted together, these two will cross and produce some really beautiful variations.

Rock penstemon is a summer-blooming perennial. It produces red blooms from June through August and many times into October. This penstemon likes rocky, well-drained soils and is a great plant for dry areas and rocky hillsides. Rock penstemon is low-growing with a spreading habit and is evergreen in North Central Texas. To keep it looking well groomed, a light shearing in spring is sufficient. It is unusual for this penstemon to reseed. Do not plant this perennial in wet areas.

Onions Top

How did the Texas 1015 get its name?
It was based on the prime planting date for the onion, which is October 15th. Onions bulb according to day length and temperature. There are many varieties available so onions can be planted during different times of the year to bulb and be harvested over many different times of the year. Having the name Texas 1015 was a way to make it easy for people to know when to plant this variety in South Texas and similar areas around the world.

Why does cutting an onion make you cry?
Onions contain several sulfur compounds. The major ones are thiopropanal S-oxide, Methyl propyl disulfide, dipropyl disulfide and propyl propenyl disulfide. The onion also contains an enzyme allinase. When you cut an onion you break the cells and the enzyme mixes with thiopropanal S-oxide and creates a volatile sulfur that gets into your eyes and causes an irritation which in turn causes tearing.

If you bite into an onion the same thing happens and causes a slight irritation to mouth tissues. An uncut onion has no pungency or tearing effect because the enzyme and sulfur are separate. To demonstrate this either freeze or heat an onion to kill the enzyme, then cut or taste and you will not experience any tearing or pungency. Microwaving is a very easy way to kill the enzyme.

What is the tallest tree in Parker County? Top
Thanks to Courtney Blevins, CF
Regional Urban Forester
Texas Forest Service, Ft. Worth
Source: http://www.waymarking.com/

Texas State Champion Pecan
N 32° 48.453 W 097° 46.705
14S E 614365 N 3630612
Quick Description: Largest pecan tree in the State of Texas
Location: Texas, United States
Date listed: 7/30/2006 8:26:23 PM
Long Description: This awesome tree was the National Champion until a slightly larger specimen was found in Tennessee a couple of years ago. Tree is on private property (farm) and can not be accessed without contacting the owners first. They are very proud of their tree though and welcome visitors. Owners are approx. 4 miles north of Weatherford, TX on Hwy. 51. You need to call the owner to set up a visit. Mr. Bill Finch at 817.467.0102
Genus/Species: Carya illinoensis

Height: 90
Girth: 22
Method of obtaining height: Clinometer
Method of obtaining girth: Tape
Location type: Private property

Information on Gaura, please. Top

Gaura lindheimeri (Pink Gaura, Butterfly Gaura, Whirling Butterflies, Wand Flower, Bee Blossom)
Curtosey of: Alliance for Water Awareness and Conservation (AWAC)
By Janet Kornbluth

Desert natives that bloom all summer are special. Fast-growing pink-white or pink Gaura blooms not only in the summer, but begins its show in the spring and extends it well to the frost. Rising above a compact base of lance-shaped leaves, on tall wiry stems that move with every breeze, the delicate four-petal flowers resemble flittering butterflies.

Since the “Butterfly” flower does attract real butterflies, the observer can sometimes see white butterflies dancing around the white petals as if the flowers themselves have just taken wing – a magical thing to behold. Gaura thrives in all zones of the desert, but in the coldest areas it dies back to the ground in winter and reemerges in the spring in standard perennial fashion.

Because of its delicate texture and light color, the original pink-white Guara tends to visually fade out if planted in a more open desert space. Therefore, it looks most handsome when contrasted against a bright or dark background, such as a boldly-painted wall or a dark green shrub. Some of the new cultivars are more brightly hued and have no problem standing out in the desert landscape.

Until about ten years ago very few gardeners knew of the existence of white Gaura lindheimeri. It started out as a somewhat overlooked plant from the wilds of Texas-Louisiana-Central Mexico. However, one day in 1994 in the Siskiyou Rare Plant Nursery of Medford, Oregon, an employee found a sport of deep maroon buds opening into bright reddish-pink flowers. It was named Siskiyou Pink. Within three years Siskiyou Pink had made Gaura lindheimeri very popular on the West Coast, and the flower is now becoming a cottage garden classic throughout the United States and the world. One major reason for Gaura’s success is the fact that it grows in virtually any climate and soil and in full or part sun. Extreme heat, extreme cold, extreme humidity, and extreme dryness do not bother Gaura. In addition, this hardy plant has no particular pests or diseases, except for the occasional aphid in stem tips.

Since Siskiyou Pink emerged, the hybridizers have been busily creating new cultivars of this all-purpose gem. From the first wild Gaura that grows to about 40” tall by 24” wide, there are now many available forms, in many shades of whites, pinks, and maroons, and ranging in sizes from 12 inches tall up to 7 feet tall! Some new Gauras have more spreading habit. Some have larger, brighter blossoms on more compact stems. Others have variation in the foliage, such as dark green leaves, dark crimson leaves, grey-green leaves bordered with white, or leaves that are variegated with green and yellow. Look for such names as Whirling Butterflies, Crimson Butterflies, Sunny Butterflies, Blushing Butterflies, Siskiyou Pink, Karalee Pink, Karalee White, Passionate Pink, Pink Cloud, Old Faithful, Pink Lady, Corrie’s Gold, Douphin, and The Bride. Of special note is the extravagant 7’ tall Old Faithful, which has been described as a “geyser of refined foliage and abundant flowers’. Undoubtedly more exciting forms are being created as this article is being written.

For those who favor a romantic flower garden in the desert, Gaura lindheimeri is the perfect perennial. For a classic flower border, Gaura can be combined with other summer-blooming perennials, like Coreopsis, Chocolate Flower, Pineleaf Penstemmon, Margerita Bop Penstemmon, Russian Sage, and Cosmos. White Guara next to the giant white flowers and bold dark leaves of the Sacred Datura makes a dramatic statement. Gaura also looks wonderful planted around roses, as its airy texture contrasts nicely with the rose’s larger leaves and flowers. Pink Gauras under pink roses create a truly sumptuous display of color. Gaura also gives a rich, softening look to stones and rocks. In the fall, it can accompany the waving seedheads of ornamental native grasses, like the blue and sideoats grama grasses, for an informal meadow effect. More formally it can complement the larger Muhlenbergia bunch grasses like Deergrass, Regal Mist and Autumn Glow. This long-blooming perennial also thrives in containers. Versatile Gaura lends itself to limitless possibilities of garden design in the High Desert.

Gaura grows in either full or partial sun and in sandy, clay or loamy soil. Unlike many natives, it appreciates some richness in the soil, so digging a small amount of amendment into the planting hole will help the new plant to flourish. It requires no laborious deadheading, but a simple mid-summer shearing of the flower stalks can revitalize and extend the growing season. As with many herbaceous perennials, cutting the plant down to the ground in late winter prepares it for the new spring growth.

Should the enthusiastic gardener wish to increase his plant material, he can do so by way of seeds and cuttings. In particular, the white Gaura easily self-seeds, creating volunteer seedlings that can be dug up and potted for further growth. In addition, stem cuttings can be dipped in hormone rooting powder and inserted into potting soil to make new rootings. The best results happen when air temperatures are between 60-80 degrees F.

To establish a Guara in the High Desert garden, one standard practice is to water the new plant once a day for the first two weeks after planting, and then once a week thereafter through the first summer. New additions to the garden can be planted this way even in the middle of summer. In the second year, Gauras can be watered as little as twice a month with proper mulching. The deeper the root system, the more drought tolerant Gauras become. However, keeping an eye on plants in their second year helps to determine the right watering frequency. All of the marvelous Gauras mentioned can be viewed on the internet and ordered to be delivered by mail during the prime shipping months (usually spring). We all deserve to grow and enjoy this beautiful Southwest native that has found its place in the gardening world.

For more information on recommended perennials for Parker County, see the real dirt A Gardening Handbook for Parker County

What is humus? Top

It is the dark brown, almost black substance that results from the decay of organic matter in the soil or in the compost pile. It also gives soil a certain sponginess and helps it retain water. Humus is also full of microorganisms that help break down various chemicals in the soil so they can be absorbed by plants. Make sure your soil has a healthy humus content by adding organic matter in the form of compost, shredded leaves, hay, straw or grass clippings to your flower and vegetable gardens on a regular basis, ideally once or twice a year.

Why are tomatoes really fruit but we think of them as vegetables? Top

In 1893, the Supreme Court ruled that the tomato must be considered a vegetable, even though, botanically, it is a fruit. Because vegetables and fruits were subject to different import duties, it was necessary to define it as one or the other. A tomato was declared to be a vegetable because they were commonly eaten as one.

To really figure out if a tomato is a fruit or vegetable, you need to know what makes a fruit a fruit, and a vegetable a vegetable. The big question to ask is, does it have seeds? If the answer is yes, then technically, you have a fruit. Generally, a fleshy growth originating from a flower and carry seeds is considered a fruit. So gourds, cucumbers, pea pods, squash, green beans and walnuts are fruit too.

A potato fails because it does not come from the flower and is part of the root. Vegetables such as, radishes, celery, carrots, and lettuce do not have seeds (that are part of what we eat) so they are grouped as vegetables.

Certain fruits like tomatoes and green beans will probably always be referred to as "vegetables" in today's society.

What is the planting date for tomatoes in Parker County? Top

Tomato transplants should not be planted until after the last normal freeze/frost date in Parker County. In spring the best dates are between March 25th and April 15th. If you have planted them and an unusually late freeze/frost does occur, you must give them protection.

If you are planning a fall garden, the suggested planting dates are between July 1st and July 25th.

More information about tomatoes and vegetable gardening in Parker County is available in the real dirt A Gardening Handbook for Parker County

Please give more information on Gulf Stream Nandinas and how they are propagated? Top

Dwarf Nandina, 'Gulf Stream'
Latin: Nandina domestica

From an article by: Gerald Klingaman, retired
Extension Horticulturist - Ornamentals
Extension News - December 8, 2000

The dwarf forms of the plant (Nandina domestica) are more recent in origin. They began showing up in the nursery trade in a big way after WWII.

'Gulf Stream' is one of a bevy of 25 or so dwarf nandinas on the market. It originated as a bud sport at Hines Nursery in Houston from the original dwarf form, 'Atropurpurea Nana,' which is a truly ugly plant with a thicket of upright stems. Gulf Stream has the triply pinnately compound leaves of the species. It produces blue-green summer foliage and bright red leaves in the fall and winter.

Being evergreen, this shrub will hold its leaves through the winter with the color persisting until new growth resumes. Gulf Stream does not seem to flower or fruit, a decided drawback because the red wintertime berries are one of the most appealing aspects of nandinas.

(Gulf Stream nandinas were) originally propagated only by division. Tissue culture techniques, the propagation procedure where plants are grown aseptically in test tubes, was perfected, and almost overnight the dwarfs went from interesting novelties to landscape minion status.

What makes the dwarf nandinas popular in the landscape is their ability to survive parched or wet planting sites with almost equal success. They also give a good winter color display of bright red, at least in most years, and they are insect and disease free. Also, their midget size allows them to fit well in smaller landscapes.

Note: You can learn more about nandinas in the June 2006 featured article and in the real dirt A Gardening Handbook for Parker County

Are the berries of yaupon hollies poisonous? Top

"POISONOUS" HOLLIES
by Richard E Bir
Taken from Auburn University Website

Recently I have had phone calls from Extension agents and Green Industry professionals in 3 states asking about "poisonous" hollies in the landscape. I am not sure what stimulated this sudden interest but will share what I learned. Please remember, I am neither a pharmacologist nor a toxicologist and I certainly have done no human feeding or dose response studies. That sort of work seems more appropriate for the medical community than for a horticulturist.

Plants That Poison by Schmutz and Hamilton states that the poisonous parts on hollies are the berries. "The berries of all species are reported to be poisonous if eaten in quantity. The toxic principle is ilicin. Although not considered very poisonous, the attractive red or black berries should be considered dangerous to small children [and animals]." Symptoms listed are "nausea, vomiting, diarrhea and stupor due to depression of the central nervous system." They also note, "These are the hollies used extensively as Christmas decorations. Indians and early settlers used the leaves to make a mild brew such as 'yaupon tea'."

Common Poisonous Plants and Mushrooms of North America by Turner and Szczawinski, gave a more thorough treatment. In the section on English holly (Ilex aquifolium) and related species, they write "Berries and leaves may cause digestive upset; berries occasional cause of poisoning in children, but not known to be fatal." They say the berries and leaves contain theobromine, a caffeine-like alkaloid listing the same toxicity symptoms as Shmutz and Hamilton. "However, fatalities from holly are unknown, and their poisonous properties are frequently overstated. Mild doses of the leaves or berries cause stimulation of the central nervous system, whereas higher doses cause depression of the central nervous system." If large quantities of the berries have been ingested, they suggest that vomiting be induced followed by activated charcoal and a saline cathartic, excess stimulation caused by theobromine can be countered with barbiturates and benzodiazipines. Obviously, medical professionals need to be involved if treatment becomes necessary.

When I checked for specific toxicity references to our common landscape hollies, I found almost nothing. For the native evergreen species besides Yaupon holly, Ilex opaca, I. cassine, I. glabra and deciduous species, I. decidua and I. Verticillata, I found that the leaves of I. cassine were sometimes used by Native Americans like the leaves of I. vomitoria to make black drink. There were no other references uncovered that indicated these native species have any toxicity at all.

It seems that rather than panicking if holly berries or leaves are ingested, we should remember that Turner wrote, "Fatalities are unknown and their poisonous properties are frequently overstated." In my search only a few species were listed as having medicinal uses. If your callers cannot watch what their toddlers [or animals] are eating, they probably have much more to fear from common beverages, condiments and household chemicals than from hollies in their landscape.

How do you propagate weeping yaupon hollies? Top

They are propagated by cuttings. Learn more in this December 2006 featured article.

Information about grayleaf cotoneaster please. Top

Grayleaf cotoneaster – Cotoneaster glaucophylla is a sprawling three or four foot, semi-evergreen shrub (depending on the winter temperatures) with dusty gray-green foliage and orange fruit that does well in Parker County. It is heat-tolerant and can tolerate sun to full or partial shade. Be aware it is especially susceptible to fire blight and leaf rollers.

Information about fertilizing pansies/violas, please. Top

Apply a light application of fertilizer to established pansy and viola (Johnny Jump-up) plantings. Use one-half pound of ammonium sulfate per 100 square feet of bed area. Repeat the application every 4 to 6 weeks, depending on rainfall. Dried blood meal or cottonseed meal are also excellent sources of fertilizer for pansies and violas. Be sure to water well after applying fertilizers.

How do you propagate Hesperaloe parvifolia? Top

Hesperaloe parvifolia, Red Yucca, is a member of the Agave family. This native Texas plant is not really a yucca and the blooms are really a coral rose color. This being said, it is still a wonderful plant for Parker County gardens. Propagate by dividing the rhizomes and offsets. They can also be started from ripe seeds in the fall.

You can find more information about Red Yucca and other shrubs that do well in Parker County in the real dirt A Gardening Handbook for Parker County

Information about Buxus microphylla japonica, please. Top

Known as Japanese boxwood, this is a compact evergreen shrub with lighter green leaves. The resistance to heat, alkaline soils as well as diseases and insects justifies their popularity. In extremely cold winters, boxwoods may suffer leaf burn but will recover quickly. Trim and shape them after the threat of a hard freeze has passed.

Microphylla koreana 'Wintergreen' is a form of boxwood that has darker green foliage and also does well in Parker County.

More information on this shrub and others that do well in Parker County can be found in the real dirt A Gardening Handbook for Parker County

What do the three numbers on fertilizers mean? Top

Most plants feed primarily on three nutrients - nitrogen (N), phosphorous (K) and potassium (P). Three numbers represent these nutrients on fertilizer bags. You might see the numbers 24-6-12, meaning the bag contains 24% nitrogen, 6% phosphorous and 12% potassium. Many of the fertilizers we recommend are listed as 3-1-2 or 4-1-2 and are considered all purpose fertilizers. But you will see rates on various bags of fertilizers such as 15-30-15, 29-3-4, 20-20-20, etc. Some plants require special rates and perform better if given the correct fertilizer. There are even fertilizers that are pure nitrogen (24-0-0) for lawns and landscapes that have tested high in phosphorus.

Nitrogen is important because it helps with vigorous growth and produces lots of leafy foliage. It is ideal for grass, but not for tomatoes, because this would cause the plant to produce lots of leaves and not much fruit.

The middle number is phosphorus, and it's important in the production of blooms and fruit. This is useful for feeding perennials and vegetables.

The last number is potassium. This is good for strong root and stem development.

What is the best way to water tomato plants and how much? Top

Water must be available in sufficient quantities for healthy growth. Most vegetables do not like wet feet, but they all must have water on a regular basis. The most efficient means of watering is a drip irrigation system. More water can be applied to the roots where it is needed by a drip system and there is less loss to evaporation than by any other method. In some areas of Parker County, this system will not work as well because the iron and calcium in the well water tends to clog up the emitters after a year or two. Since the tubing is relatively inexpensive, some people replace it every couple of years.

Water only when it is needed. When the top one-inch of soil is dry, it is time to water. Water long enough so that the moisture will penetrate to a depth of six inches. Check the soil moisture every two or three days and water as needed.

Information from the real dirt A Gardening Handbook for Parker County. This is the handbook where you will find more information about vegetable gardening in Parker County such as recommended varieties and other steps that will insure you enjoy your gardening.

Do Nellie R Stevens hollies require much water? Top

Shrubs and trees require help their first year and Nellie R Stevens hollies are no different. They do not require any heroics but do not let them dry out because just one time of extreme dryness can lead to terminal wilt for the plant. Once established, the Nellie R Stevens holly can deal with the demands Parker County weather makes on them. It is a quality plant and should be considered for Parker County landscapes. In time of limited rainfall, you will need to supplement with water to help the plants in your landscape.

Find more about Nellie R Stevens holly and other shrubs for Parker County in the real dirt A Gardening Handbook for Parker County

Is there a benefit to adding ammonium sulfate to abelia? Top

See St Augustine, ammonium sulfate because this applies for shrubs as well as all the landscape

Gnats in my houseplants, help! Top

I have two containers of ivy and assortments that have gnats in them. What's the cause? I'm thinking that watering is probably the problem. What should we do? I've now got the plants on the patio and I'm hesitant to bring them in the house because I don't want any gnats in the house. I'm thinking I need to spray the entire plant with some kind of spray, but what?

A lot of the time these are fungal gnats and are caused from over watering or water remaining in the saucer or bottom of the pot. I would take them out and repot them with new soil. This will do away with their "home-like conditions" then it should be ok. You could put them back in the same pot, after you have washed the pot. You could give them a drench with Safer houseplant spray and try to get rid of them but I think getting rid of the contaminated soil is the best. Sometimes they also gather in the saucer when there is water left in it. Hopes this helps.

Information please on expanded shale and its use. Top

Horticulture Update
November-December 2003
Texas AgriLife Extension Service, Texas A&M University, College Station, Texas
Expanded Shale - A new Possibility for Amending Clay Soil
by Dr. Douglas F. Welsh, Professor & Landscape Horticulturist, Texas A&M University

A form of expanded shale is now available to gardeners that will be useful in loosening tight clay soils and making them more workable.

'Blue Shale' from the Midway Shale formation is present in a pattern across Texas through Corsicana to Texarkana and stopping near Laredo. It is usually found 10-15 feet underground. It was formed during Cretaceous times when Texas was a large lakebed and the lakebed sediments solidified under pressure into the present-day shale formation.

Jack Sinclair of TXI Industries has explained that the shale is mined and ground to 1" to l/2" range particles and then kiln fired. As it progresses through the kiln for 40 minutes at 2,000 degrees C, certain chemical processes take place in the silica content (60-70%) causing the material to expand. The expansion of Kitty Litter (calcined clay), for example, occurs at only 800-900 degrees.

As the material cools, cavities are left after gases escape, leaving a porous lightweight chunk capable of absorbing water and releasing it slowly at a later time.

Recommendations for using expanded shale with containerized plants call for putting one-third of the material in the bottom, then mixing the expanded shale with potting soil 50-50 for the rest of the pot.

For flower beds with sticky or gumbo-type soil, Dr. Steve George of the Texas AgriLife Extension Service recommends putting down 3 inches of expanded shale on top of the area, and tilling it in six to eight inches deep. Also add 3 inches of finished, plant-based compost as well, which results in a 6-inch raised bed. Crown the bed to further improve water drainage.

Dr. George also remarked:

"Based on a two-year research study and six years of field trials, I feel that expanded shale will open up and aerate heavy, sticky clay soils faster than any material that I have ever tested. Due to its porous nature, it provides aeration from within the shale particles and, in poorly aerated clay soils, resulted in a more extensive and healthier root system than did other treatments being tested. Even though I dearly love finished, plant-based compost, if I were limited to only one application of one soil amendment with which to open up heavy clay soils, I would take expanded shale and never look back!"

Several trials are underway at the present time to test the long-term effects of using expanded shale. Last June Dr. Frank Allen and the city of Duncanville laid out perennial flower beds in black gumbo and the city of Carrolton (situated on Blackland Prairie soils) is working on field trials with Dr. Steve George. Trials include working with black gumbo only, lava sand with gumbo, compost with Blackland soil, and compost and expanded shale in existing soil. It is anticipated that the lightweight material might create a permanent physical change in the blackland soil (or, according to Dr. George, last at least 10 years as a conservative estimate).

The amendment is now sold by the TXI Corporation under the brand name 'Tru-Grow.' It may be purchased in the Dallas/Fort Worth, Houston, and Navasota areas. Check with local garden centers and suppliers for availability in your area.

Additional Note: Clear Fork Materials in Aledo, Texas have it in bulk and in bags. Stuart Nursery at 2317 Fort Worth Highway in Parker County carries it in bags.

How do you trim Weeping Yaupon Holly? Top

Be very careful when pruning Weeping Yaupon Holly Ilex vomitoria 'Pendula' or you will loose the prized look of the plant. It needs little pruning to develop a strong structure. Weeping Yaupon Holly makes a distinct irregular, weeping form with its upright crooked trunks and slender, curved, branches with small, oval, gray-green foliage.

They can reach a height of 30-feet or more but most you see are between 15 to 20-feet with a width of 6 to 12-feet. As the tree grows older next to a sidewalk or patio, lower branches can be removed to allow room to walk under them.

Why are the leaves on my azaleas turning brown and the plants looking stressed? Top

There are no blooming plants that are more beautiful than a sweep of azaleas, where they can be grown. Parker County does not happen to be one of those places unless you are prepared to do extraordinary bed preparation and continue with special care for their life expectancy. This is an instance when you will have fewer headaches by choosing plants that are native or adapted to our area.

If you choose to plant azaleas, you may want to plant them in pots where the soil can be monitored (should be planted in equal amounts of brown sphagnum peat moss and shredded bark mulch). Give them morning sun and afternoon shade; water them regularly because the porous mix will dry out rapidly. Be prepared to water more often than you would if the plants were set directly in the soil.

Azaleas can range from 2 to 6 feet so think about choosing plants that have a similar look for your landscape. The following are plants you may want to consider for your landscape. Some can be used in place of azaleas and some do not have that look but will work well in Parker County.

Region 4 - North Central Texas (Dallas, Ft. Worth, Denton, Wichita Falls)
Note - Plants with number 7 are adaptable to most areas of Texas