Perennial Ryegrass Seed Rate and Calculator
Perennial ryegrass is the cool-season grass where two extension services print different new-lawn bands. This page keeps both, and it does not invent a germination time.
Result: perennial ryegrass seed
New lawn, 5,000 square feet. The cited band is 4 to 5 pounds per 1,000 square feet.
Virginia Cooperative Extension lists 3 to 5 pounds for a new lawn.
How Much Perennial Ryegrass Seed Per 1,000 Square Feet?
Penn State Extension lists 4 to 5 pounds per 1,000 square feet for a new lawn. That is the band the calculator uses.
Virginia Cooperative Extension lists 3 to 5 pounds for a new lawn of the same grass. The wider band is shown beside the Penn State figure, not averaged into a third number.
Purdue Extension AY-20 lists a mowing height of 2.5 to 3.5 inches, shared with Kentucky bluegrass on that sheet. Germination days for perennial ryegrass are not on the rows we can cite, so the cell says not verified. An overseeding rate is not verified either.
| Project | lb per 1,000 sq ft | Source |
|---|---|---|
| New lawn | 4 to 5 (calculator). Virginia lists 3 to 5 | Penn State Extension; Virginia Cooperative Extension |
| Overseeding | Not verified | Not verified |
Perennial Ryegrass Seed Needed by Lawn Size
Built from the rate table above: lawn size divided by 1,000, times the rate. Acre rows use 43,560 square feet per acre.
| Lawn size | New lawn | Overseed |
|---|---|---|
| 1,000 sq ft | 4 to 5 | Not verified |
| 5,000 sq ft | 20 to 25 | Not verified |
| 10,000 sq ft | 40 to 50 | Not verified |
| 20,000 sq ft | 80 to 100 | Not verified |
| 0.25 acre | 43.6 to 54.5 | Not verified |
| 0.5 acre | 87.1 to 108.9 | Not verified |
| 1 acre | 174.2 to 217.8 | Not verified |
Perennial Ryegrass Mowing Height and Germination Time
Mowing height is included only because Purdue Extension AY-20 lists it for this grass. Germination is included only when that sheet lists it.
| Measure | Value |
|---|---|
| Mowing height | 2.5 to 3.5 inches |
| Germination time | Not verified |
Perennial Ryegrass Compared With Tall Fescue and Kentucky Bluegrass
Tall fescue's new-lawn band is heavier, and its mowing band starts higher. Kentucky bluegrass is lighter to seed and shares this 2.5 to 3.5 inch mowing band. Only bluegrass, of those two neighbors, has a cited germination span here.
| Item | Perennial RyegrassRyegrass | Tall FescueFescue | Kentucky BluegrassBluegrass |
|---|---|---|---|
| Season | Cool | Cool | Cool |
| New-lawn rate, lb per 1,000 sq ft | 4 to 5 | 6 to 8 | 2 to 3 |
| Mowing height | 2.5 to 3.5 in | 3 to 4 in | 2.5 to 3.5 in |
Common Perennial Ryegrass Seeding Mistakes
- Averaging 4 to 5 with 3 to 5 into one invented midpoint. Both bands stay visible.
- Copying the tall fescue germination window onto ryegrass. That number is not cited for this grass.
- Filling an overseed from half of the new-lawn rate. That half-rate note is cited for tall fescue and Kentucky bluegrass, not here.
Related Lawn Calculators
Perennial Ryegrass Seed Rate and Calculator FAQ
What new-lawn rate does Penn State list for perennial ryegrass?
4 to 5 pounds per 1,000 square feet. Seeding rate: Penn State Extension; Virginia Cooperative Extension.
What new-lawn rate does Virginia Cooperative Extension list for perennial ryegrass?
3 to 5 pounds per 1,000 square feet. The calculator still uses the Penn State band of 4 to 5.
Is a germination time listed for perennial ryegrass?
No. That figure is not verified. The mowing height that is listed is 2.5 to 3.5 inches, from Purdue Extension AY-20.