Preparing the Garden for Winter
Dr. Mario A. Villarino. County extension agent for agricultural and natural resources in Hopkins County.
Fall Fertilization of your lawn. Fall fertilization is the key to prolonging fall color and promoting early springs recovery of lawns. It also helps to produce a dense turf which resists winter weeds. Texas AgriLife Extension Turf Specialist recommend fertilizers used in the fall to be high in nitrogen and potassium and low in phosphorus. A 2-1-2, 3-1-2 or 4-1-2 analysis is preferred over a balanced fertilizer such as a 12-12-12 for fall application. Grass fertilized in the fall with nitrogen and potassium have shown greater survival during winter months and faster spring recovery than grasses fertilized with high phosphorus materials in the fall. Avoid using straight soluble nitrogen fertilizers such as ammonium sulfate or urea during late fall because they increase the susceptibility to disease and winterkill. Make fall applications in October. Application rates should not exceed 2 pounds of nitrogen per 1,000 square feet.
Type of Fertilizer
Choice of the type and grade of fertilizer material to use depends on soil test recommendations. In every fertilizer analysis (such as 12-4 8), the first number represents the percent nitrogen (N), the second number represents the percent phosphorus (P2O5) and the third number represents the percent potassium (K2O). A complete fertilizer can be used in accordance with soil test results for the fall and following spring applications. If you have done your soil test and need further assistance interpreting the laboratory results, please given me a call. I will be more than glad to help with a proper fertilizer selection. Additional nitrogen needed between the fall and spring applications for complete fertilizer can be supplied from one of several sources. Slowly available sources of nitrogen, such as ureaformaldehyde, IBDU, processed sewage sludge or cottonseed meal, are more desirable for summer applications of nitrogen than soluble sources such as ammonium nitrate, urea or ammonium sulfate. Slow-release and organic fertilizers usually cost more, but they are available to the grass over a longer period of time and help avoid the excessive growth produced by soluble nitrogen fertilizers. Soluble nitrogen sources should be applied in small amounts and more frequently than slowly soluble or slow-release types. Also, soluble nitrogen fertilizers are more likely to burn the grass than slow-release nitrogen fertilizers.
Plant selection for fall-winter
October is the month for planting cold hardy fall annuals which bloom profusely the following spring. This concept is a hard item to sell to most people who are convinced that customarily "April showers bring May flowers", therefore, they don't consider planting until April. Nature, on the other hand, doesn't need convincing that fall IS the best and proper time for planting winter annuals. A number of spring- blooming wildflowers germinate in the fall, their tops remaining small and inconspicuous while developing a massive root system throughout the winter, then provide us with a riot of color during April and May. The bluebonnet is one of these. Although heat is needed to germinate the seed, cool weather is needed to develop the bluebonnet's root structure. The clue to successfully cultivating bluebonnets lies in a knowledge of the seed. The seeds resemble small, flat pea- gravel and are multi-colored with slate blue and light tan being the most common hues. People can now buy bluebonnet seed which will germinate and begin growing within ten days rather than the months required previously. One might think that any seed, if viable, will grow when planted; not so with the bluebonnet. Nature has structured the bluebonnet seed in such a way that only a small percentage of the seed germinates during the first season after planting. This delayed germination ensures species survival during periods of adverse growing conditions such as prolonged drought. Nature may want to ration bluebonnet seed germination but planters of the state flower want each and every seed to germinate and grow rapidly. To ensure rapid, high percentage germination, the bluebonnet seed has to be treated to remove inhibiting properties of the seed coat which otherwise prevent water uptake and the initiation of growth. This process of seed treatment is referred to as scarification. Seed which has been properly scarified will germinate within 10 days after planting in a moist soil. Seedlings of scarified seed are also more vigorous. For years, wildflower lovers have planted bluebonnet seed and wondered what happened to the beautiful spring bloom which they expected.
First of all, if common bluebonnet seed is used which has not been chemically treated (scarified), one doesn't have much chance for success. The germination of non-scarified seed is sometimes less than 20 percent. This means that assuming you do everything correctly (pest control, optimum moisture), one could only expect, at best, 20 seeds to grow out of every 100 planted using non-scarified seed. Also, one can't even expect all of those 20 seeds to sprout simultaneously as sprouting may occur over a 30 day period. The availability of chemically scarified seed solves this age-old problem.
Of course, getting seed to germinate and plants to emerge from the soil is just the beginning. To insure success you must have first chosen the optimum planting site. Emerging seedlings must be protected from the ravages of pillbugs and rotting by soil fungi. Most would-be bluebonnet growers kill plants with too much water. Remember, bluebonnets are actually very drought tolerant and as such are very susceptible to death from overwatering.
To avoid possible problems with seed germination, many people will want to use transplants instead. Transplants, being older, tougher plants, are much easier to handle and establish. The transplant is also easier to space so that stand establishment in formal plantings is assured. Transplants as well as scarified seed of white, pink, and 'Worthington Blue' bluebonnets are available to accentuate and complement the beauty of the more common blue variety.
One way to ensure successful bluebonnet bloom from seed or transplants is to plant them in an ideal location. Ideal can be defined with one word, sunny. Bluebonnets will not perform well if grown in the shade or in an area which receives less than 8-10 hours of direct sunlight. If grown in a shaded area, the plant will be tall and spindly with few blooms.
Bluebonnets will thrive in any soil as long as it is well drained. If you are plagued with a sticky clay soil, try building raised (6 inches or more) planting beds and amending the soil with 3-4 inches of organic matter (compost, tree leaves, spoiled hay, etc.) Don't keep the soil too wet; just keep it slightly moist. Remember that once plants become established (two or three weeks after planting), they are drought tolerant and one of Texas' toughest natives.
Damping-off, a fungal disease complex which causes stem rotting, is not as prevalent with tough-stemmed transplants as with tender, emerging seedlings. To minimize damping-off, avoid planting in beds with a history of this condition, use transplants rather than seed and do not over water.
Also remember that during early growth, bluebonnets form ground-hugging rosettes. The whole plant may not be over several inches tall but the leaves may cover an area the size of a dinner plate. This is a natural condition and regardless of how much one waters or fertilizes, the plant will not grow rapidly until the warmth of spring initiates flower stalks. It is also natural for the lower leaves to turn a crimson color after the first freeze. Beneath the rosette of leaves, a large mass of roots is growing. These roots have the ability to form nitrogen-fixing nodules which are filled with beneficial bacteria that can take nitrogen from the atmosphere and feed the plant. This means that fertilization can also be kept to a minimum. No additional fertilizer needs to be added to bluebonnet planting beds since most established planting beds have an abundance of plant nutrients remaining from fertilization of previous crops.
When actually planting bluebonnet seed, FORGET THE IDEA OF JUST THROWING OR SCATTERING THE SEED IN THE GRASS! Much bluebonnet seed has been wasted as bird feed using this scattering technique. The seed MUST be lightly covered or raked into the soil. In naturalized fields of bluebonnets, the seed is gradually covered by washing soil and defoliation of weeds and grass, BUT IT IS COVERED BEFORE IT ACTUALLY GERMINATES.
When planting a bluebonnet transplant, be careful not to plant it too deeply. You will notice that all of the leaves arise from a central crown-like structure. This crown should not be buried, otherwise the plant will rot.
Major enemies of seedlings and transplants are small, nocturnal menaces referred to as pillbugs, rolly-pollys, sowbugs, and several other names which should not be mentioned in polite company.
These hungry devils can devour plants overnight. Many times the devastating onslaught does not occur immediately after planting. To ensure seedling and transplant survival, it is wise to broadcast pillbug bait around the newly established or emerging plants and do so weekly during the first month after planting.
ADD PANSIES FOR WINTER COLOR
Many would-be, patriotic planters of bluebonnets have been discouraged with the idea of a non-blooming winter bluebonnet plant. From September until April, bluebonnets are a hard sell item to those who demand beauty from flower beds all year. This problem can be solved by interplanting with other fall annuals which serve as companion plants to provide interim beauty. After several years of testing and some record-breaking cold winters, the recommended companion plants for bluebonnets are pansies, dusty miller, dianthus, spring-flowering bulbs (tulips, etc.), ornamental cabbage or kale and Drummond red phlox. Most of these flowering plants will be overgrown by the bluebonnets in March as they begin to expand. At that time, remnants of the interim annuals can be removed, thus allowing the bluebonnets to take center stage.
To ensure continuous beauty and utilize the texture of the bluebonnet foliage as a background, plant bluebonnet transplants in rows 24 inches apart. Transplants should be 12 inches or less apart in the row. Then between each row of bluebonnets, or every 12 inches, plant a row of pansies, ornamental kale, cabbage, dianthus, dusty miller, spring-blooming bulbs or Drummond red phlox. Bluebonnets also make a great companion plants for summer blooming perennials such as lantana, mealy cup sage, autumn sage, and Michalmas daisy. These and similar plants can be cut to the ground after the first frost and interplanted with bluebonnet transplants. As the bluebonnets fade in late spring, they can be removed as the warm season perennials begin to emerge. In addition, bluebonnets make great plants for containers such as whiskey barrels and terracotta pots. The pots should be filled with a potting mix which drains well and placed in a sunny location. Bluebonnets are an ideal low maintenance flower with which to replace summer color container plants (copper plants, periwinkles, purslane)--particularly those around decks, patios and pools which won't be used again until spring. The following spring, as the bluebonnets fade, replace them with your favorite heat loving flowers. To keep bluebonnets blooming longer, remove old blossoms. This encourages a profusion of side shoots to develop and bloom while eliminating seed production which would otherwise stop the bloom cycle.
For maximum impact and beauty in the landscape, use large drifts of a single color rather than a hodge-podge sprinkling of many colors. For example, a line of blue pansies (interplanted with one color of bluebonnets) reinforcing the line of your patio is most striking. Cool colors such as blue make an area appear farther away, whereas reds and yellows bring an area closer.
Bluebonnet planting time is also important. Many people wait until they see bluebonnet plants blooming in the spring to begin planting. IT'S TOO LATE to plant transplants in the spring. Fall is the optimum time! The sooner in the fall chemically-scarified seed and transplants are planted, the larger the plants will grow in the spring and subsequently more bloom will occur. Root systems of seedlings and transplants established in early fall expand more and are able to produce a larger plant when top growth and bloom begins in the spring. Transplants should be planted no later than Halloween in North Texas.
For more information on this or other gardening topics, please contact the Hopkins county Extension Office by calling 903-885-3443.