September is the best time to seed cool-season grasses.
Seeding New Lawns
o Use good quality, certified seed; avoid seed with significant levels of
“weed” and “other crop.
o Use recommended seeding rates and distribute well. Seeding at a rate
higher than recommended can cause issues with disease and
environmental stress.
o Good seed to soil contact is critical! Aeration prior
to seeding is one way to promote this. Topdressing
and raking to cover seed are some other methods
of enhancing seed to soil contact. Thatch build-up
will hinder seed to soil contact. See core-aerating
below is thatch is a problem in your lawn.
o Light, frequent irrigation is necessary the first few
weeks after planting and may be required several
times daily depending upon weather. Soil should
remain moist but not waterlogged.
o Minimize traffic on the area until seedlings are
ready to be mowed. Begin mowing once seedlings reach 3-4 inches tall.
Overseeding an Existing Lawn
o Prior to planting, mow the area low (1 to 1-1/2 inches) to reduce
competition with seedlings and help improve seed contact with soil.
o Apply fertilizer based on soil test results or use starter fertilizer at rate
recommended on the bag.
o Water light, but often keeping soil moist but not waterlogged.
Fertilize cool-season grasses.
o Use a quick-release source of nitrogen.
o Apply 1 to 1-1/2 pounds of actual nitrogen per 1,000 square feet.
Core-aerating
o Removes cores of soil to relieve compaction, speed up thatch
decomposition and improve water, nutrient and oxygen movement in soil.
o Soil should be moist but not saturated.
o Holes should be 2-3 inches apart and 2.5 to 3 inches deep.
o Cores can be left on the surface and will break down naturally
