Lawn and Garden Update is a publication of the Departments of Soil and Crop Sciences & Horticultural Sciences, Texas Agricultural Extension Service, The Texas A&M University System, College Station, TX. Contributing Editors: Drs. Gene R. Taylor, William C. Welch, and Douglas F. Welsh. Douglas F. Welsh, Editor November/December 1998


Plant of the Holiday Season: Passion Flower
Lawn Care
Christmas Gifts for Gardeners
For a Red Rerun . . .
Live Christmas Trees
Garden Checklist

PLANT OF THE HOLIDAY SEASON: Passion Flower, Passiflora

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

Passion Flower is a woody vine that has unusual blossoms. Roman Catholic priests of the late 1500s named it for the Passion (suffering and death) of Jesus Christ. They believed that several parts of the plant, including the petals, rays, and sepals, symbolized features of the Passion. The flower's five petals and five petal-like sepals represented the 10 apostles who remained faithful to Jesus throughout the Passion. The circle of hairlike rays above the petals suggested the crown of thorns that Jesus wore on the day of his death. The priests who named the vine found it growing in what is now Latin America.

Today, gardeners in many parts of the world raise passion flowers for the blossoms. The flowers may be almost any color. Their diameter ranges from 1/2 to 6 inches. Most of the approximately 400 species of passion flowers grow in warm regions of North and South America. The maypop, the common passion flower of the Southern United States, bears a yellow fruit. This fruit tastes slightly sour or very sweet, depending on the species. Passion flowers grown for passion-fruit juice are Passiflora edulis flavicarpa.


This article is excerpted from "The Composting Slide Set," produced by County Extension Horticulturists Skip Richter, Vince Mannino, and Nowell Adams, and Extension Specialist Marty Baker for the aggie-horticulture web site. Major editorial contributions were made by Sam Cotner and Dan Lineberger.

One time-tested method of turning ╬trash' into ╬treasure' is home composting. Interest in composting is increasing dramatically. The early Greeks and Romans practiced composting, although the process itself has occurred in nature since the beginning of time. Whether an ancient art or a modern science, composting is a useful and environmentally sound gardening practice.

What is Composting?
Composting is nature's own recycling program! In forests and meadows, tree leaves and other organic material form a carpet over the soil surface. In time, naturally-occurring organisms break down or decompose this layer. Compost is the rich, dark, crumbly material that results; in essence, it is nature's own nutrient-rich slow-release fertilizer.

Why Compost?
Yard waste makes up 20 to 50 percent of curb-side garbage. Composting landscape and kitchen wastes at home reduces the volume of curb-side solid waste. This saves transportation and disposal costs while providing an environmentally sound alternative.

Compost is a valuable soil amendment. It can be used to:

+ Enrich soil with nutrients
+ Help sandy soils retain moisture and add nutrients
+ Loosen tight, heavy clay soils
+ Mix with potting soil for container-grown plants
+ To mulch around landscape plants.

If you have a garden, lawn, trees, shrubs, or even planter boxes or house plants, you have a use for compost.

What Can be Composted?
You can compost kitchen waste, leaves and grass clippings, as well as other yard waste such as pine needles, weeds, small or chipped prunings, and spent garden plants. Shredding the material first, although not required, makes for faster composting. Avoid composting diseased or insect-infested plants, noxious weeds, and kitchen wastes containing meat, dairy products, cooking oil, or grease.

How to Compost
For composting, you can use traditional free-standing compost heaps or homemade or manufactured bins. A bin or some type of enclosure may save space and be more attractive. There are a variety of manufactured composting bins available from garden catalogs or retail stores. Designs and prices vary considerably, but they do offer a quick-start way of composting. Make a homemade compost bin from a number of materials, including wire fencing, lumber, used pallets, and cement blocks. Whatever materials you use, it's important to design the bin to allow for good air movement and easy accessibility for turning the pile and removing the finished compost. So, if you use a bin, choose materials and a design to suit yourself and your needs for neatness, appearance, economy, performance, and access. Ideally, your compost pile or bin should be 3 to 5 feet in diameter. With any pile or bin, it's best to start the compost in several layers. The microorganisms that turn yard waste into compost need the proper balance of nitrogen and carbon materials in their ╬diet'. Alternate 6- to 8-inch layers of high-carbon materials (such as leaves and other dry plant debris) with layers of high-nitrogen material (such as grass clippings, kitchen water, or manure). Add Fertilizer. When such materials are unavailable, a sprinkler or fertilizer can provide the nitrogen. Add Soil. Follow this with a shovelful or two of compost or garden soil, to add the microorganisms necessary for decomposition. Add Water. Moisten each layer as you stack it. If you don't moisten the pile as you build it, it will be difficult to effectively do so later. Repeat Layers. Repeat layers until the pile is about 4 feet high. Afterwards, water enough to keep the pile moist but not wet. Turning. Turn the pile weekly to thoroughly mix the materials. Turning allows for thorough decomposition and speeds up the composting process. The basic ingredients in making compost are water, air, and soil or compost to introduce microorganisms. The mixture of these ingredients is important. Too much or too little can slow the composting process and cause other problems as well.

Here are some ways to tell if your compost is progressing well.
+ If the pile is composting properly, the interior should heat up to at least 140 degrees Fahrenheit.
+ If the pile fails to heat up, composting is still progressing, but very slowly, and may take six months to a year or more to be completed.
+ If your compost is damp and warm only in the middle, the pile may be too small. Collect more material and mix the old ingredients into a new pile.
+ If the heap is damp and sweet-smelling but still will not heat up, it's short on nitrogen. Simply mix in a nitrogen source such as fresh grass clippings, fresh manure, or nitrogen fertilizer.
+ If the center of the pile is dry, you may have too much coarse, woody material and not enough water. Chop or shred the course material, add fresh green waste, and then turn and moisten all the ingredients.
+ Finally, if the compost has a bad odor, the pile is probably too wet and not getting enough air. In this case, add coarse dry materials and mix well.

In-The-Garden Composting
There are many methods of in-the-garden composting, one of which is ╬walkway' composting. Place a thick layer of leaves, shredded branch trimmings, garden wastes, and grass clippings between the rows of raised-bed vegetable gardens. If grass clippings are used, they should be partially dried or applied in a thin layer, to avoid offensive odors. This makes an excellent all-weather walkway that will allow you to work in your garden during wet periods. As these materials decompose and compact, add more to the surface. In a few months, this material will be largely decomposed and ready for mixing into the garden soil. A second option, called ╬sheet composting', involves rotor-tilling a few inches of leaves into the garden in the fall. A light scattering of fertilizer will help speed the process along. By the following spring, these leaves will be decomposed, leaving a rich, easy-to-work soil ready for planting. Large amounts of leaves may be easily mixed into the soil by repeating the spreading and rotor-tilling steps, one layer at a time

Trench Composting
Another method of composting involves the use of trenches. This method works well for vegetable gardens, especially if you don't have a space for a compost pile or bin. Dig trenches deep enough to accommodate the volume of waste to be composted. Build next season's new planting beds on top on the trenches, and dig new trenches in place of the old beds. By alternating trenches and garden rows each season, you'll improve the soil throughout your garden. And, you'll see improved results in your garden harvest.

╬Compost-holing' is a variation of the trench method, useful for small quantities of kitchen wastes. Dig a hole 12 to 18 inches deep, using a shovel or post-hole digger. Alternate layers of kitchen scraps and an inch or two of soil until the hole is filled.

Whatever method of composting you choose, you can effectively recycle your yard and kitchen waste into some of the best soil-building products available.


By Dr. Gene R. Taylor, Department of Soil & Crop Sciences, Texas A&M University

Lawn Fertilization for Winter Hardiness.
Fall is the time when Texans should consider fertilizing their warm season lawns for the winter. The ability of a lawn to survive a bitterly cold or long winter, or one that fluctuates between cold and warm, can be directly impacted by early fall and winter fertilization practices. A sound fall fertility program can help ensure a smooth spring green-up, and reduce the chance of winter kill. Proper fall fertilization may also reduce the impact of diseases, such as brown patch on St. Augustine, and spring dead spot on intensively-managed Bermudagrass lawns. To help warm season grasses prepare for the winter, it is recommended that a low nitrogen, high potassium fertilizer be applied in early fall while the grass is still actively growing. During the fall months, when day lengths are shortening, the growth habits of warm season grasses change from primarily leaf production to the production and storage of carbohydrates. These carbohydrates are stored in the rhizomes, stolons, and roots until spring green-up, when they are utilized to produce new growth. Excessive nitrogen in the fall may encourage leaf production at the expense of carbohydrate storage. Potassium plays an important role in protecting plant cells from freeze injury, and is therefore required in higher quantities. To meet the demands for low nitrogen and high potassium, use fertilizers with a 1-1-2 (N-P-K) ratio. An example of a fertilizer with this ratio is 5-5-10. Ten pounds of 5-5-10 per 1000 square feet of turf is sufficient to meet the early fall needs of the turfgrass. In late fall and early winter when growth has stopped, an application of 1.0 pound of readily available nitrogen per 1000 square feet of turf, in the form of a 3-1-2 ratio, aids in early spring green-up of St. Augustinegrass lawns. Also, early winter fertilization may help maintain green color, especially for St. Augustinegrass in south Texas where winter temperatures are not usually low enough to induce dormancy. Application of potassium during the winter on St. Augustinegrass has not been proven to increase freeze resistance, while too much phosphorous may actually increase the susceptibility of St. Augustinegrass to winter kill. Research at North Carolina State and Texas A&M University found that freeze resistance in Bermudagrass lawns was highest with a late fall/early winter application of a fertilizer with a 4-1-6 ratio, at a rate of 1.0 pounds of nitrogen per 1000 square feet of turf.

Winter Overseeding of Lawns.
Now that winter is just around the corner, many Texans are wondering what they can do to maintain a green lawn all year long. For most people, winter is a time of rest from the weekly job of mowing. But for others, the desire to have a green landscape year round is too great. Their best remedy is to overseed their warm season lawns with a cool season grass. The practice of overseeding is not new. Golf courses and athletic fields have been overseeding for years to increase both aesthetic quality and playability. Winter overseeding is relatively simple to do, and can add significant beauty to a landscape. However, it can also cause problems for the warm season lawn the following spring. The process of winter overseeding involves seeding a cool season grass into an existing warm season lawn. Planting of the cool season grass is done in the fall when soil temperatures at a 4-inch depth average 74 degrees F. Annual ryegrass is the most commonly used grass for overseeding home lawns. Perennial ryegrass, Poa trivialis (rough stalk bluegrass) and creeping bentgrass are used for overseeding in intensively managed turf, such as golf course greens and athletic fields. However, these grass species are not usually recommended for use on home lawns. A proper seeding rate for Annual ryegrass in a home lawn setting should range from 4 to 6 pounds of seed per 1000 square feet of turf. Very little site preparation or cultivation is required for overseeding. A home owner should get an acceptable stand of winter grass by simply spreading the Annual ryegrass seed over the existing lawn. Lowering the mowing heights on the warm season lawn in the fall, after the grass has significantly slowed its growth, will help ensure a good stand. Care should be taken to not cut off too much of the warm season grass (i.e., scalp the lawn to the dirt). For Bermudagrass and Zoysiagrasses, a mowing height of 3/4 to 1 inch is acceptable, while 2 inches is low enough for St. Augustinegrass. Remove any extra clippings, and then broadcast the Annual ryegrass seed. Be careful to avoid spreading grass seed into planting beds and mulched areas. A broadcast spreader works well for large open areas of the lawn, but a drop spreader should be used to seed near landscape plantings or any other areas where you don't want weeds in the future. Once you have spread the seed, enhance the seed-to-soil contact by lightly raking with a leaf rake or dragging a flexible mat over the lawn (a small section of old carpet or chain link fence works well). Then, lightly water daily for 5 to 7 days. After the newly planted seed has sprouted, fertilize with 1/2 to 1.0 pound of readily available nitrogen per 1000 square feet of turf. A fertilizer with a 3-1-2 ratio, like 15-5-10, applied at rate of 3.0 to 6.0 pounds per 1000 square feet of turf, will provide the seedlings with the nitrogen and phosphorous they need during establishment. Once the Annual ryegrass is established, apply ammonium sulfate (21-0-0) every 45 days, at a rate of 2.5 to 5.0 pounds of fertilizer per 1000 square feet of turf, to maintain actively growing grass. Mowing should be on an as-needed basis throughout the winter, and should follow the 1/3 rule: never remove more than 1/3 of the leaf blade in a single mowing. A sharp mower blade will help to maintain an even green color. A dull blade will tear and shred the grass blades, leaving the lawn with a dull brown color on the leaf tips. While not usually a problem in home lawns, overseeded grass can compete with the warm season grass in the spring for light, water, and nutrients. This extra competition for the warm season grass may slow the spring green-up of the lawn.


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

With the arrival of December, the minds and thoughts of even the most avid gardener turn away from the yard and garden toward Christmas and the holiday season. Gardening chores are temporarily laid aside as the sights and sounds of Christmas fill the air. If you have gardening friends on your gift list this year, consider surprising them with a 'green thumb' type of gift, which can be used and enjoyed year-round as they pursue their favorite hobby. Garden items make unusual, welcome, and unique gifts, and the selections are vast. There is something for nearly everyone in any price range. The following gift suggestions may just fit into your gardener's stocking this Christmas.

1. Garden Tools. From a hand trowel to a riding lawn mower, gardening tools are guaranteed to please. Consider one of the many time- and work-saving electric lawn or garden products. There are many from which to choose.

2. Garden Accessories. Many unique and interesting objects fall into the garden accessory group. Sculpture for the patio or garden can last for years. Or, you may choose to be more casual, with wind chimes, a bird feeder, flower pots, or hanging baskets.

3. Gardening Books and Magazines. Although the selection of gardening books is wide, choose a book that is adaptable to the recipient's interest. One of the popular monthly gardening magazines will be appreciated throughout the year.

4. Garden Plants. Although seldom considered, outdoor plants can make welcome gifts. The Christmas season is ideal for planting all major trees and shrubs. You might want to consider a pecan or fruit tree for your gardening friend. Select one which will complement the recipient's landscape. Regardless of the choice, plants make a delightful and lasting gift.

5. A Gift Certificate. If all else fails, why not consider slipping a gift certificate into the stocking of the 'green thumber'? Your local nursery or garden center will be most happy to fulfill your wishes here.


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

Larkspurs have naturalized in nearly all areas of Texas and are known for their tall spikes of blue or purple flowers. Pink, white, and double forms are also available, but the seed seems to revert to the dark blue or purple single form after a few years.

Larkspurs are fall-seeded annuals that prefer to be left in place after germination. They are spectacular and easily grown. A sunny location and well-drained soil of moderate fertility are the major requirements. Thinning the seedlings in mid winter to about 8 to 10 inches apart will usually result in an impressive display of individual plants that can reach 3 to 4 feet tall. Like poppies and other fall-planted annuals, larkspurs usually need little supplemental irrigation, since they complete their life cycle during our naturally cool, moist seasons. Whether seed is collected or allowed to fall and naturally germinate in the garden, it is important to remember that modern hybrid varieties often do not come true from open, pollinated seed. Seed saved from many of these modern types may have little resemblance to the original flower. Large and double flowers may return as smaller single types, and bright colors may tend to be more muted. Annuals that reseed and return year after year can be as valuable as perennials to the garden.

There is something special about these plants that like your garden so well that they choose to come back each year for another visit. In addition to convenience and economy, reseeding annuals such as larkspurs often add charm and special character, since they frequently come up in places where we may not have planted them, adding informality and spontaneity to the garden. Since larkspurs respond well to cultivation and fertilization, it may be necessary to work the soil and add organic material and fertilizer after the seed has fallen. This cultivation process may destroy some of the seeds by planting them too deeply, but there is usually a sufficient number remaining to provide plenty of plants for the next season. A frequent problem with reseeding annuals is over-germination and, therefore, crowding, to the point that plants cannot grow and produce properly. This requires careful observation in the garden to check on young seedlings so that when they reach a size large enough, they may be transplanted or thinned. Most young seedlings may be successfully transplanted when they put on their second set of leaves. Some annuals, such as poppies and larkspurs, are somewhat difficult to transplant and do best when thinned and allowed to mature where they germinated. Young seedlings of flowering annuals may show little resemblance to the mature plants and be very difficult to distinguish from weeds. This requires practice and patience until the young seedlings of desired annuals become familiar. It also implies that most preemergent herbicides and heavy mulches cannot be used in areas where reseeding annuals are desired. The mulches and herbicides are just as effective in controlling the desirable annuals as they are the weeds.

After larkspurs have completed their flowering season in late spring, they may be replaced with hot-season annuals, such as Globe Amaranth (Bachelor Buttons), periwinkles, celosias, or purslanes.

Back by popular request: FOR A RED RERUN . . .

Excerpt from an article about the Ellison Tourism and Gift Center [808 S. Horton Street, Brenham, TX 77833, (409) 836-0084] which appeared in "Weekend Gardener," November/December 1996.

With patience, you can coax your poinsettia to bloom again for another year, according to Ellen Ellison of the Ellison greenhouses in Brenham, Texas. Here's how:

Christmas. Pick a colorful plant with tightly clustered yellow buds. Protect from hot or cold drafts, water when dry, and place in a room with enough natural light for reading.

New Year's. Apply all-purpose house plant fertilizer. Continue light, water, and fertilizer. Plant should remain colorful for many weeks.

Valentine's day. Do nothing unless your plant has become long and leggy. If it has, prune to 5 inches from the soil.

St. Patrick's Day. Remove faded and dried parts of the plant. Add more soil, preferably a commercially-available sterile mix.

Memorial Day. Poinsettia should be around 3 feet high. Trim off 2 or 3 inches from ends of branches, to promote side branching. Re-pot to larger container. Move plant outside . . . first to indirect, then direct light.

Fourth of July. Trim plant again. Make sure it has full sunlight. Slightly increase the amount of fertilizer. If you would like root cuttings, they will root easily if kept warm.

Labor Day. Poinsettia may have grown to 5 feet or more. Move indoors, but make sure it has 6 hours of direct light from an uncurtained window. Reduce fertilizer.

First Day of Autumn. Starting on or near September 21, give plant 13 hours of uninterrupted darkness and 11 hours of bright light per day. Keep night temperatures in the lower 60s. Continue to water and fertil

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