Gardening tasks for August

Much of the August list of garden tasks is taken from the OSU Extension Publication, HLA-6408—Landscape Maintenance Schedule with additional information added. This maintenance schedule is a checklist which emphasizes prevention rather than remediation. Some of the topics mentioned below have individual Fact sheets available at


Irrigated warm-season lawns may be fertilized again (HLA-6420).

Brown patch disease of cool-season grasses can be a problem.

Continue to meet water requirements of turf.

For areas being converted to tall fescue this fall, begin spraying bermudagrass with glyphosate products in early August (HLA-6419 & 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) More information can be found at

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).

Trees and shrubs

Young trees and shrubs may be fertilized again.

Watch for a second generation of fall webworm in late-August-early-September. A good article by Julia Laughlin on bagworms and webworms is available at

If you had bagworms on shrubs or trees in the summer, continue to inspect them and remove any remaining bagworms. Males emerge from their bags in early fall and search for bags containing females. After mating, the female lays several hundred egg. She then leaves the bag and dies while the eggs remain in the bag until they hatch the next May. More information on controlling bagworms is available in Entfact 440 available at

Shrubs and flowers

Hedges and shrubs can be pruned, if necessary, about mid-August.

Water all plantings thoroughly unless rainfall has been adequate.

Discontinue deadheading roses by mid-August to help initiate winter hardiness.


The fall vegetable garden is planted now. More information about fall planting can be found in Fall Gardening Fact Sheet HLA 6009 available at Also, just doing a Google search by typing in HLA6009 will bring up the fact sheet. If you want to print it, choose the pdf version.

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