- Water all plantings thoroughly unless rainfall has been adequate. It is better to water more in depth, less often and early in the morning.
- The fall vegetable garden may be planted now. (*HLA-6009)
- Divide and replant spring blooming perennials like irises, peonies, and daylilies if needed.
- Irrigated warm-season lawns may be fertilized again. (*HLA-6420)
- Hedges and shrubs can be pruned, if necessary, about mid-August.
- Young trees and shrubs may be fertilized again.
- Discontinue dead-heading roses by mid-august to help initiate winter hardiness.
- Brown patch disease of cool-season grasses can be a problem. (*HLA-6420)
- Meet water requirements of turf. (*HLA-6420)
- For areas being converted to tall fescue this fall, begin spraying bermudagrass with glyphosate products in early-August. (*HLA-6419 and *HLA-6421)
- White grub damage can become visible this month. Apply appropriate soil insecticide if white grubs are a problem. Water product into soil. (*EPP-7306)
- Watch for a second generation of fall webworm in late August/early-September.
- Pre-emergent herbicides for winter-annual weed control in warm-season grasses can be applied in late-August. Water in the product after application. (*HLA-6421)
General
Water your compost during extremely dry periods so that it remains active.
Always follow directions on both synthetic and natural pesticide products.
Watch for high populations of caterpillars, aphids, spider mites, thrips, scales, and other insects on plant material in the garden and landscape and treat as needed. (*EPP-7306)
Fall fescue should be mowed at 3” during the hot summers and even up to 3 ½“ if growing under heavier shade. Warm season lawns like Bermudagrass and Zoysia-grass should be gradually raised to around 2”- 2 ½” to better adjust for heat stress and the onset of fall.
Avoid late applications of fertilizer on woody plants at this time. The next best time to fertilize woody plants will be mid to late October.
Vegetables
August is a good month to start your fall vegetable garden. Bush beans, cucumbers, and summer squash can be replanted for another crop. Beets, broccoli, carrots, potatoes, lettuce, and other cool season crops can also be planted at this time.
Soak vegetable seed overnight prior to planting. Once planted, cover them with compost to avoid soil crusting. Mulching will keep planting bed moist and provide shade during initial establishment of vegetables. Monitor and control insect pests that prevent a good start of plants in your fall garden.
*Fact sheets may be obtained from your local Oklahoma Cooperative Extension Office or on line at http://osufacts.okstate.edu
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