How to Plant a Tree in Oklahoma Soil

Become a Master Gardener

Classes start in September each year. Register at our office on 15th Street for more information.

Garden

• You have all of September to plant cool-season vegetables like spinach, leaf lettuce, mustard and radishes, and until the middle of September to plant rutabagas, Swiss chard, garlic and turnips. Click here for Fall Gardening Guide.

Lawn

• Last nitrogen fertilizer application of the year on warm-season grasses should be applied no later than September 15. (HLA-6420)
• Winter broadleaf weeds like dandelion will begin to emerge in late September, which is also the best time to control them with a 2, 4-D type herbicide.
• If pre-emergent control of winter-annual weeds (henbit, chickweed, annual bluegrass, etc.) is desired in lawns, the application should be completed by the second week of September. Note: Do not treat areas that will be seeded in the fall.
• Continue bermudagrass spray program with glyphosate products for areas being converted over to tall fescue this fall.
• Plan to seed bluegrass, fescue or ryegrass as needed in shady areas in mid- to late-September. Fall is the best time to establish cool-season lawns (HLA-6419).
• White grub damage can become visible this month. Apply appropriate soil insecticide if white grubs are a problem (EPP-7306). Water product into soil.

Landscape

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Infestations of fall armyworms have been observed in bermudagrass in area pastures since mid to late July, and it seems subsequent moth flights are producing larvae that may be poised to invade lawns, golf courses, sod farms, and other landscapes. Fall armyworm populations reaching densities of 10 to 15 larvae per square foot have been observed in research plots of tall fescue at the OSU Botanical Gardens.

Fall armyworms are surface-dwelling "climbing cutworm" caterpillars. They prefer to eat grasses, and often go unnoticed until they become large and their feeding damage becomes evident. Fall armyworms tend to prefer tall fescue, but they also feed on bermudagrass and other turfgrass species. Larvae develop through 6 instars. One generation of fall armyworm can develop in about 18-28 days, depending on temperature, and infestations may occur until the first "killing frost". In Oklahoma, there are 2-3 generations present from late July through late October. Fall armyworm cannot overwinter in Oklahoma, hence its arrival later in the growing season.

Mature fall armyworms measure 1� inches long when fully grown. Their body color can range from green to brown or black, and they have a distinct stripe along each side of the body. Their head capsule has a prominent, inverted, white "Y" at the front. A magnifying glass or hand lens may be needed to see this characteristic on smaller larvae. Small larvae do not consume the entire leaf tissue but instead scrape off all green tissue, leaving a clear membrane that gives the leaf blade a "window pane" appearance. Larger larvae (4th through 6th instars) can chew through the entire leaf.

Feeding activity by flocks of birds can serve as a sign that armyworms are present. Fall armyworms can be detected through close examination of the turf, or by using a soapy water flush. A soapy water flush involves mixing 1 tablespoon of lemon-scented dish soap per gallon of water and pouring the solution over several small areas of damaged turf. If present, larvae should be visible within 30 to 60 seconds as they become irritated by the soapy water and leave their hiding places in the thatch.

Homeowners should carefully consider the need to control fall armyworms before taking action. Some cool-season turfgrass could recover from a fall armyworm infestation late in the year without treatment, and bermudagrass and zoysiagrass lawns may be only slightly damaged and not warrant treatment. However, early indications this year suggest chemical treatment will be needed in many areas, especially for protecting cool-season turfgrass.

There are many insecticides that are registered for control of fall armyworms that can provide excellent control. Note that products containing microbial active ingredients (i.e., Bt and spinosad) should be applied when caterpillars are small for maximum effectiveness. If choosing between granular and liquid applications, keep in mind that granular products are a bit slower acting, and require watering for activation. As always, read the insecticide label for important information about using the product safely and effectively.

Want a low maintenance, beautiful and reliable plant for your garden that returns every year?  Try some peonies in the back of a border. For spontaneity, exuberance and beauty, few perennials can surpass peonies. Each spring, this hardy perennial comes up from just a few roots to become a sturdy, shrub like plant with dense, leathery foliage and dozens of exquisite flowers. They are native to Asia, Southern Europe and our Pacific Northwest. Once planted, a peony may live for decades. Peonies make wonderful cut flowers in spring arrangements. They usually bloom about the same time as tall bearded iris.

When to plant: Peonies may be planted in the fall any time before the ground freezes. Spring planting is not recommended because the plants begin their top-growth before the roots have become well established.

Where to plant: Select sunny and well drained location where they will receive at least a half-day of sunshine. The best blooms usually are found on plants growing in full sun. Do not plant near large trees or heavy shrubs where they would be robbed of moisture and nutrients. Because of their large blossoms, peonies are at their best when grown in large groups to create a mass of color. After blooming, these dark green glossy plants provide a perfect backdrop for other shorter perennials and annuals. Mulching around plants will help in retaining vital moisture.

Disbudding: Most varieties of peonies develop several small side buds near the base of the terminal or end bud. If large flowers are desired, the side buds should be removed so that the plant's strength will all be directed to the terminal bud.

Staking: If the flower head is large and heavy, the stem may not be able to support its weight.  Watch closely in spring as green shoots emerge from the ground...it is much easier to properly locate the stake prior to the plant developing branches and leaves. Carefully place a hoop-type stake or wire support around the plant before too much growth emerges.  
What to expect: Do not be discouraged the first and second year after planting if the growth is low and slow to develop. It may or may not bloom during this time. Be patient, as it may take three years before the plant produces the expected blooms.

Why Peonies Do Not Bloom: The most common cause is that the root was planted too deeply. In our climate, the red eyes (sprouts) on the root should be placed no more than � to 1 inch below ground level for best flowering. Peonies do not transplant well when mature, so plant them in a spot where they will stay.

Fall Care: After the first heavy frost, trim away dead leaves and stems, cutting them down even with the ground. Do not put in compost pile as they may contain disease.

Fairy Rings sound like something out of a fairy tale, which might be interesting or entertaining to some, but not so much to you as a gardener if they are in your yard. Fairy rings are actually produced by many varieties of underground fungi. Fairy ring damage appears in a target pattern.  They typically expand from a central point into an arc or circle and are particularly noticeable when they grow in our lawns. The appearance is variable and may occur in essentially all types of lawn grasses. While they are most notably a ring of small, tan mushrooms, they may also appear as either green or brown rings. The grass in these rings or circles may be greener than any other grass in your lawn. They can range in size from a few inches to several hundred feet in diameter, and may persist for years.

Fairy rings typically occur from late spring to early fall and can disfigure a lawn. The fungus feeds on organic matter in the soil. Sometimes as it feeds, it frees up nutrient nitrogen in the organics, thus creating dark green rings in lawns. However, many times this organic matter is the result of a tree that died some time ago or old, buried wood that is simply decomposing. The decomposition feeds the fungus, thus creating the mushrooms. The fungus is especially problematic in acid soils. As the mushroom fungus multiplies, its white underground growth (mycelium) becomes so dense and tough that water cannot penetrate the lawn. Starved and thirsty as weather warms up, grass around the mushrooms may die. The resultant mushrooms or puffballs may appear overnight, particularly after a rain, and should be removed as soon as possible.    
 
So, what to do about it? Well, management of this is not easy. If possible, remove old tree roots and stumps or buried wood. Be sure to pick all mushrooms before caps open up and release spores. Apply lawn fertilizer containing nitrogen to revitalize fairy ring center and aerate soil during the growing season. Finally, ample deep watering can help to minimize the loss of grass due to the fungal dehydration, along with more frequent mowing. There are fungicides labeled for fairy ring control, but they usually require a certified professional for application. If grass is lost, reseeding may be necessary. The only real option for complete elimination of the fungus is to remove and replace both the soil and the grass.