Question 1

How much grass seed do I need?

Accepted Answer

Divide the lawn area by 1,000 and multiply by the seeding rate for your grass type. A 1,500 ft² lawn in tall fescue at 8 lb per 1,000 ft² needs 12 lb of seed for a new planting, or 6 lb for overseeding.

Question 2

What is the seeding rate for tall fescue?

Accepted Answer

Six to eight pounds per 1,000 square feet for a new lawn, three to four for overseeding. Tall fescue seed is large, so it takes more weight to reach the same seed count as a fine-seeded grass.

Question 3

Why does bluegrass need so much less seed?

Accepted Answer

Seed size. Kentucky bluegrass has roughly 2 million seeds per pound against 230,000 for tall fescue, so 2.5 lb of bluegrass puts down more seeds than 8 lb of fescue. It also spreads by rhizomes, filling in gaps the seeding missed.

Question 4

When should I plant grass seed?

Accepted Answer

Late summer to early autumn for cool-season grasses — soil is warm, nights are cooling, and weed competition has passed. Late spring to early summer for warm-season grasses like bermuda and zoysia. Spring seeding of cool-season grass usually loses to crabgrass.

Question 5

Can I use too much grass seed?

Accepted Answer

Yes, and it is a common mistake. Overseeded plots germinate densely and then thin out from competition, leaving weaker plants with shallower roots than a correctly seeded lawn. More seed does not produce a thicker lawn.

Question 6

How long does grass seed take to germinate?

Accepted Answer

Perennial rye in 5 to 10 days, tall fescue 7 to 14, and Kentucky bluegrass 14 to 30. Mixes containing rye look like they are working first, because the rye is up while the bluegrass is still below ground.

Question 7

Do I need to cover grass seed?

Accepted Answer

Light cover helps — a quarter inch of compost or straw retains moisture and keeps birds off. Do not bury it. Most grass seed needs light to germinate and will fail if it is more than about a quarter inch deep.

Question 8

How much should I water new grass seed?

Accepted Answer

Lightly and often — enough to keep the top inch damp, usually two or three times a day in warm weather, until germination. Then move to deeper, less frequent watering. Seed that dries out once after imbibing water dies.

Grass Seed Calculator

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