Answer: The following is a month-by-month guide for the care of cool- and warm-season grasses, compiled by Kansas State University Research and Extension. Cool-season grasses include tall fescue, perennial ryegrass, and Kentucky bluegrass and warm-season grasses include bermuda, zoysia and buffalograss.
March ? Both warm- and cool-season grasses: If necessary, spot treat broadleaf weeds on a day that is 50 degrees F or warmer. Irrigation or rain within 24 hours of applying the treatment will reduce its effectiveness.
April ? Both warm- and cool-season grasses: Between April 1-15 or when the Eastern Redbud is in full bloom, crabgrass preventer should be applied. If a product with Barricade (prodiamine) is being used, apply two weeks earlier. Crabgrass preventers need to be watered before they will start to work. Follow label directions on when to make the next application (probably before June 15).
May ? Cool-season grasses: To improve ?looks? apply a slow-release fertilizer. If there are broadleaf weeds (dandelions) use a combination product that will kill the broadleaves as well as fertilize and remember not to water it until 24 hours after application.
Warm-season grasses: More applications will give a deeper green color, but will increase mowing, They can also lead to a build-up of thatch with bermudagrass and zoyiagrass.
The fertilizer ratio to use is 1 pound of nitrogen per 1,000 square feet per application: Bermuda - 2 to 4 applications, Zoysia - 1 to 3 applications, and Buffalograss - 1 or 2 applications.
June ? Both warm- and cool-season grasses: If grubs have been a problem in the past, consider applying a product containing ?Merit? or ?Mach 2". Both insecticides are effective and safe and must be watered in before they become active.
Warm-season grasses only: This is a good time to core aerate which will help alleviate compaction, increase the rate of water infiltration, improve soil air exchange and help control thatch.
Late July-August ? Both warm- and cool-season: It?s too late to use ?Merit? or ?Mach 2,? so if there is grub damage, apply a grub killer and water immediately.
September ? Both warm- and cool-season grasses: Spray for broadleaf weeds, if they are a problem. Choose a day when air temperatures are at least 50 degrees F and rain (or irrigation) isn't likely within 24 hours.
Cool-season grasses only: Fertilize lawn around Labor Day. This fertilizer does not need to be a slow release. If soil tests call for phosphorus or potassium, apply fertilizer after core aerating.
Late October ? Both warm- and cool-season grasses: If broadleaf weeds are a problem, be sure to spray. Pick a day that is at least 50 degrees F. Irrigation or rain within 24 hours of applying the treatment will reduce its effectiveness.
Note: On all products listed above, use the rates listed on the labels.
Best wishes with your lawn.
Q&A Library Searching Tips