Each issue includes a monthly checklist for suggested garden activities along with articles on gardening topics and profiles of plants especially suitable for Texas and the South. Another feature of the publication is information about forthcoming educational opportunities sponsored by the Texas Agricultural Extension Service.
Dr. William C. Welch and I share editorial responsibilities for the newsletter. Articles from County Extension Agents (Horticulture), and Specialists in related disciplines are welcome and encouraged. Bill and I are both Extension Horticulturists in the Department of Horticultural Sciences at Texas A&M University.
You may click on a title below to read an individual article (and print out only that article), or you may scroll down to read the entire newsletter.
- Poinsettia - Plant of the Month for November/December
- New Year’s Resolutions for the Gardener and 'Yardener'
- Plan in Winter for Butterflies and Caterpillars in Your Garden
- Roses in the Fall Landscape by Dr. William C. Welch
- The Licensed Irrigator Program in Texas by Guy Phipps
- New Brochures from Texas Water Savers
- Irrigation Best Management Practices
- Landscape Improvements (Soil, Mulch, and Maintenance)
- Lawn Maintenance Best Management Practices
- It's A Great Time To Have Your Soil Tested by Dr. Samuel D. Cotner
- Dividing Your Perennials in Winter by Cynthia W. Mueller
- Texas Citrus Is Now In Season by Cynthia W. Mueller
- Garden Checklist for November-December 2000 by Dr. William C. Welch
Poinsettia: Plant of the Month
The History
Native to Mexico, the poinsettia originated in a region near the present-day city of Taxco. Joel Robert Poinsett, a Southern plantation owner and botanist, was appointed the first United States Ambassador to Mexico (1825-1829). While visiting Taxco, he was struck by the beauty of the brilliant red plants he found blooming in the region during December. He had some of the plants sent to his plantation in Greenville, South Carolina, where they flourished in his greenhouse. While the botanical name, Euphorbia pulcherrima, was given by a German taxonomist in 1833, the common name, poinsettia, became and has remained the accepted name in English-speaking countries. With over 70 million plants sold nationwide each year, the poinsettia is now the number one flowering potted plant sold in the USA.
The Myth
The widespread belief that poinsettias are poisonous is a misconception. The safety of poinsettias in the home is demonstrated in scientific studies conducted by Ohio State University in cooperation with the Society of American Florists. The study concluded that no toxicity was evident at experimental ingestion levels far exceeding those likely to occur in a home environment. In fact, the POISINDEX Information Service, the primary information resource used by most poison control centers, states that a 50-pound child would have to ingest over 500 poinsettia bracts to surpass experimental doses. Yet even at this high level, no toxicity was demonstrated. As with all ornamental plants, the poinsettia is not intended for human or animal consumption.
Bract Color
Look for plants with fully mature, thoroughly colored and expanded bracts, i.e., the colorful parts of the poinsettia. Avoid plants with too much green around the bract edges. Bracts come in white, pink, peach, yellow, marbled or speckled, as well as the traditional red. An abundance of dark, rich green foliage is a vital sign of good plant health. Look for plants with dense, plentiful foliage all the way down the stem.
Shape and Proportion
Proper proportion of plant height and shape relative to container size is the key to an aesthetically pleasing poinsettia. Plants should appear balanced, full and attractive from all angles. A generally accepted standard is that the plant should be approximately 2-1/2 times taller than the diameter of the container.
Durability and Freshness
Select plants with stiff stems, good bract and leaf retention, and no signs of wilting, breaking, or drooping. Be wary of plants displayed in paper, plastic, or mesh sleeves. A poinsettia needs its space; the longer a plant remains sleeved, the more the plant quality will deteriorate. Examine the soil of the plant. It’s best to avoid waterlogged soil, particularly if the plant appears wilted. This could be a sign of irreversible root rot. When transporting the plant, protect it from chilling winds and temperatures below 50 degrees F. Re-inserting the poinsettia into a sleeve or a large, roomy shopping bag will usually provide adequate protection for transporting the plant home when it is cold and windy.
Location and Temperature
The poinsettia thrives on indirect, natural daylight, and exposure to at least six hours daily is recommended. If direct sun cannot be avoided, diffuse with a light shade or sheer curtain. To prolong the bright color of the poinsettia bracts, daytime temperatures should not exceed 70 degrees F. Avoid placing the plants near drafts, excess heat, or the dry air from appliances, fireplaces, or ventilating ducts.
Water and Fertilizer
Poinsettias require moderately moist soil. Water the plants thoroughly when the soil surface feels dry to the touch. Remove the plant from decorative pots or covers, and water enough to completely saturate the soil. Do not allow the poinsettia to sit in any standing water; root rot could result which could kill the plant. It is not necessary to fertilize the poinsettia when it is in bloom.
Outside Placement
Since poinsettias are sensitive to cold weather, frost, and rain, outside placement during the winter months should be avoided. However, in mild climates, an enclosed patio or entry way may be suitable, provided the night temperatures do not drop below 55 degrees F. Make certain the delicate bracts are well protected from wind and cold rain.
After the Holidays
Keep the plants in indirect sun and water regularly. Place your plants outdoors, where they can bask in the warmth of spring and summer, after outside night temperatures average 55 degrees F. or above. When the bracts age and lose their aesthetic appeal, usually by late March or early April, cut the poinsettia back to about 8 inches in height. By the end of May you should see vigorous new growth. Continue regular watering during the growth period. Fertilize every 2 to 3 weeks throughout the spring, summer, and fall months with a well-balanced, complete fertilizer. Around June 1, you may transplant your poinsettias into larger pots. Select pots no more than 4 inches larger than the original inner pot. A soil mix with a considerable amount of organic matter, such as peat moss or leaf mold, is highly recommended. If you wish, you may transplant the poinsettias into a well-prepared garden bed. Be sure the planting bed is rich in organic matter and has good drainage. Pruning may be required during the summer to keep plants bushy and compact. Do not prune after September 1.
Re-flowering
The poinsettia is a photoperiodic plant, meaning that it sets bud and produces flowers as the autumn nights lengthen. The plants will naturally come into full bloom during November or December, depending upon the flowering response-time of the individual cultivar. Timing the bloom to coincide closely with the Christmas holiday can be difficult without the controlled environment of a greenhouse. Stray light of any kind, such as from outside street lights or household lamps, could delay or entirely halt the re-flowering process. Starting October 1, the plants must be kept in complete darkness for 14 continuous hours each night. Accomplish this by moving the plants to a totally dark room, or by covering them with a large box overnight. During October, November, and early December, the plants require 6 to 8 hours of bright sunlight daily, with nighttime temperatures between 60 and 70 degrees F. Temperatures outside this range may delay flowering. Continue the normal watering and fertilizer program. Following this regime for 8 to 10 weeks should result in a colorful display of blooms for the holiday season.
Top 10 New Year’s Resolutions
for the Gardener and 'Yardener'
From The Weekend Gardener
- 10 ~~~~~~~~~~
- I will use a pesticide only when absolutely necessary, and will use the least toxic one.
- 9 ~~~~~~~~~~
- I will continue to wage war on fireants by using baits, such as Amdro and Logic, in the spring and fall. I will check out the Texas Two-Step method for fireant management.
- 8 ~~~~~~~~~~
- I will not water the lawn in the middle of the day, and will only water when it needs it.
- 7 ~~~~~~~~~~
- I will prepare the soil by adding pine bark when planting shrubs and flowers, but not when planting a tree.
- 6 ~~~~~~~~~~
- I will add one new “feature” to my garden this year (i.e., a new bed, a bench, a statue, an arbor).
- 5 ~~~~~~~~~~
- I will put up a bird feeder or plant a butterfly-friendly plant.
- 4 ~~~~~~~~~~
- I will mulch all flower and shrub beds to conserve water and prevent weeds.
- 3 ~~~~~~~~~~
- I will plant at least one vegetable crop in my garden (i.e., green beans, a cherry tomato, bell peppers, a row of corn).
- 2 ~~~~~~~~~~
- I will not overprune my crape myrtles.
- 1 ~~~~~~~~~~
- I will plant a tree.
Plan In Winter For Butterflies and Caterpillars In Your Garden
Butterflies will visit, and possibly stay to lay eggs, wherever there is a variety of plants for food and shelter, some moisture, and an absence of pesticides. While there are typically more species in warm climates than in cooler ones, there are butterflies almost everywhere in the country. Their appearance in your backyard ultimately depends on whether their favorite plants are growing there - certain ones to support their larvae, many others to support adult butterflies.
Larvae (caterpillar) host plants
The typical garden is not likely to incidentally have plants that host the larvae of most butterflies. The caterpillars of each species usually favor the foliage of specific plants or plant groups at this stage of their lives. Larval host plants are often unattractive, weedy and wild, generally unpopular in cultivated gardens. Yet, adult female butterflies choose these particular plants (Monarchs must have milkweed!) to lay their eggs on. This assures that newly hatched caterpillars have appropriate food immediately at hand, or the noxious compounds from plants that repel predators.
Typically, young caterpillars begin voracious feeding immediately after hatching, virtually skeletonizing host plant foliage. Watch a parsley worm (Swallowtail) devour the foliage of Queen Anne’s Lace, carrots, or parsley. Butterfly larvae grow as they eat, shedding their skins 4 to 6 times before achieving maximum size for pupating. Only then do they desist, becoming immobile in a hard chrysalis suspended from a leaf or stem of the larval host plant until emerging as an adult butterfly.
Butterfly Host Plants
Fortunately, adult butterflies have more cosmopolitan palates. The flower nectar they need for energy is available in many different flowering plants. They will visit your yard in search of those most easily accessed by their long, coiled tongues, or proboscis, which enables them to reach deeply into the center of flowers where the glands that produce the sweet nectar are located. They are particularly attracted to hot-colored, fragrant flowers. They get further nutrition from moisture from puddles and raindrops, rotting carrion and other liquids that provide traces of minerals and nutrients not in nectar.
Butterfly Garden Design
The butterfly gardener’s challenge is to provide diversity of plants in communities throughout the property to support both larvae and adults. Variety is the key. Choose many kinds of herbs, annuals and perennials, vines, groundcovers, shrubs and trees. Assure that blooms are available to visiting butterflies for the entire season. The greater the variety of suitable plants, the greater the potential number and variety of types of butterfly visitors.
It is not necessary to integrate larval and adult plants throughout the landscape. Just allow some part of your yard or nearby property to remain weedy and undeveloped to lure female butterflies to lay eggs. Somewhere in the yard, let fresh water accumulate to support communal “mudpuddling”, so butterflies get soil salts and minerals as well as moisture. Overripe fruit that has dropped from trees also provides nutritious moisture. Finally, butterflies like some flat stones for basking, or sunbathing, to gather warmth to power their wings.
Butterflies visit flowering plants that are in full sun and in sites sheltered from wind in beds or containers. Protect garden beds exposed to the wind with a hedge of glossy abelia or butterfly bushes (Buddleia) or a wall or trellis covered with honeysuckle or passionflower. Flowering shrubs provide shelter for roosting, too. The more fragrant, the better. Plant at various heights, because like birds, certain butterfly species prefer to feed at certain heights. Some species are quite territorial and try to chase others from favorite plants.
Finally, unlike the famous monarchs which migrate to Mexico and other points south, most butterfly species overwinter nearby. This means that their eggs, chrysalises, or larvae are likely to be in or near your yard during the non-gardening months. Some will even hibernate as adults. Do not mow weedy sites and dismantle woodpiles which provide them safe shelter in the off-season.
Favorite larval host plants include asters, Bermuda grass, clover, hollyhock, lupine, mallow, marigold, milkweed, nettle/thistles, parsley, passionflower, plantain, snapdragon, sorrel, St. Augustine grass, turtlehead, and violet.
Caterpillars: Distinguishing Friend From Foe
Butterfly larvae tend to be solitary, or sparsely distributed, whereas pest caterpillars such as fall webworm make tents and hatch in the hundreds. The latter are best handled by pruning the tent out of the tree or breaking it open so that the birds can eat the immature larvae.
However, even in sparse numbers butterfly caterpillars can damage ornamentals or food plants. For example, the ubiquitous white cabbage butterfly lays eggs that turn into destructive green worms which devour cabbage and broccoli and their relatives. An insecticide product containing Bt (Bacillus thuringiensis) sprayed onto plant foliage will handle feeding worms that threaten to destroy crop yields. In the case of parsley worms on parsley, simply moving them to a non-essential plant such as wild carrot will both save the crop and preserve the eventual butterfly. (Taken in part from writings of the National Garden Bureau, Liz Ball, author).
Taken in part from writings of the National Garden Bureau, Liz Ball, author.
Roses in the Fall Landscape
By Dr. William C. Welch
Professor and Landscape Horticulturist
A photograph of ‘Mrs. B.R.Cant’ (Tea, 1901) accompanies this article. It is among the most robust of the Tea roses sometimes attaining a height and spread of 8 feet, with dozens of silver-rose petals tipped with dark rose. The flowers are full and fragrant. It blooms all during the growing season, but flower size, quality, and volume are far greater during spring and fall. Although it will occasionally be attacked by black spot disease, it will usually thrive without spraying if it is placed where air circulation and sunlight are good. Another great Tea rose very popular in Texas is ‘Mrs. Dudley Cross’(Tea, 1907). Mrs.Cross is a lovely pale yellow tinged with pink. Stems are nearly thornless, and disease resistance is excellent.
Among the best China roses for Texas gardens are ‘Old Blush’(pink), ‘Mutabilis’(yellow, pink, and crimson), and ‘Ducher’(white). ‘Old Blush’ was the favorite rose of Texas pioneers because it was tough, bloomed freely, and easily rooted from cuttings. ‘Mutabilis’ is sometimes known as the “Butterfly Rose” since a large bush in bloom resembles a cloud of butterflies. Mature China roses can reach 6 to 7 feet unless frequently pruned. ‘Ducher’ is pure white and also blooms profusely in the fall.
China and Tea roses are best adapted to the southern two thirds of the state. Winter temperatures in far North Texas and the Panhandle limit their use to areas in the garden where they can receive some winter protection during cold spells. November through February are ideal times to root roses from cuttings. Old garden roses thrive as “own root” plants and most do not need to be grafted onto a hardy rootstock to thrive. For information on rooting roses from cuttings click on Rose Propagation.
The Licensed Irrigator Program in Texas
By Guy Fipps
TAMU Extension Agricultural Engineer
Many times County Extension Offices receive questions from the public about the Texas Natural Resource Conservation Commission’s Licensed Irrigator Program. Listed below are some of the common questions associated with application and licensure:
- Who needs an irrigator’s license?
Anyone who designs, installs, consults or repairs landscape irrigation system for the general public (note: there is no corresponding program for agricultural irrigation). - Who is exempt?
Homeowners who do their own systems, employees who work on their employer’s irrigation system, plumbers and certain other professionals. - How to get a license:
Applicants must complete the “Basic Course” and pass an exam given by the TNRCC about 3 times a year. The Basic Course involves 3 to 4 days of instruction. (Note: TAEX does NOT offer the Basic Course. A list of providers can be obtained from the TNRCC, 512-239-6659, 512-239-3659; Texas Natural Resource Conservation Commission). - How to keep your license:
Licensed Irrigators must take 8 hours of continuing education units each year and pay a renewal fee.
Three New Brochures from Texas Water Savers:
- Irrigation Best Management Practices
- Landscape Improvements (Soil, Mulch, and Maintenance)
- Lawn Maintenance Best Management Practices
The Rio Star Category® combines the two reddest varieties - Rio Red and Star Ruby grapefruit. There is an overall blush on the exterior peel with deep red interior color which is 7 to 10 times redder than the Ruby Red.