LAWN CALENDAR FOR COOL SEASON
GRASSES
Lawns may be maintained at different levels of
quality according to individual preference, but good lawns seldom
"just happen." This summary outlines major steps required to
maintain a year-round high-quality lawn.
The practices refer primarily to cool-season
grasses, such as Kentucky bluegrass, perennial ryegrass, tall
fescue and fine fescue. Timing is approximate for Western
Washington; it may vary two weeks or more from one area to another
in the state or from year to year.
March
•As needed, start mowing at recommended heights
(2-2.5").
•Use broadleaf herbicides for perennial and
winter annual weeds not controlled in the fall.
•Overseed thin spots early if missed last fall.
(Do not overseed with annual ryegrass.)
•Watch for moles; traps are the only effective
means of control.
April
•Aerate if thatch is 1 inch deep or soil is
compacted.
•Use crabgrass preventers (preemergence
herbicides) by April 15. Start top-dressing low spots as grass
grows.
May
•Fertilize if needed when spring growth begins to
slow. Use a slow-release form of nitrogen, such as polymer- or
sulfur-coated urea, urea formaldehyde, or a natural organic to
improve lawn quality without promoting excessive leaf
growth.
•Apply postemergence broadleaf herbicides for
control of summer annual weeds.
•Watch for first brood of sod webworm. Apply
insecticides about 10 days after major moth flight if damage to
turf is seen.
June
•Start watering as needed. Water infrequently to
a soil depth of 6 inches. Overwatering can be harmful, but water
frequently enough to prevent drought stress. Kentucky bluegrass
under stress is susceptible to disease. Don't start watering if you
cannot continue full season.
Rapidly growing lawns need frequent mowing. Let
clippings remain unless they are excessive.
