LawnWeather

Wyoming Lawn Care Calendar

In Wyoming, crabgrass preventer typically goes down between May 8 and Jun 11: first in Sheridan, last in Laramie. Below are typical fertilizer, seeding and frost dates for Cheyenne, Casper, Sheridan and Laramie, from 2016–2025 weather data. Enter your ZIP code for this year's timing.

When to apply pre-emergent in Wyoming

Typically between May 8 and Jun 11, depending on where you live. The window opens first in Sheridan (around May 8) and last in Laramie (around May 20). Apply when soil reaches 50°F, before it stays above 55°F.

CityCrabgrass preventer window
SheridanMay 8 – Jun 1
CheyenneMay 12 – Jun 8
CasperMay 12 – May 29
LaramieMay 20 – Jun 11

Cool-season lawn calendar

Lawns across Wyoming are mostly cool-season grass (tall fescue, Kentucky bluegrass, perennial ryegrass).

CitySpring fertilizerOverseeding & seedingFall fertilizer
CheyenneJun 1 – Jul 6Jul 22 – Sep 10Aug 1 – Oct 27
CasperMay 22 – Jun 26Jul 22 – Sep 10Aug 17 – Oct 26
SheridanMay 25 – Jun 29Jul 18 – Sep 6Aug 11 – Oct 21
LaramieJun 4 – Jul 9Jul 10 – Aug 29Jul 16 – Oct 21

Frost dates in Wyoming

CityLast spring frostFirst fall frost
CheyenneMay 13Oct 5
CasperMay 11Oct 5
SheridanMay 11Oct 1
LaramieMay 25Sep 23

Median dates, 2016–2025. A dash means frost does not occur in most years.

Frequently asked questions

When should I put down pre-emergent in Wyoming?

Typically between May 8 and Jun 11, depending on where you live. The window opens first in Sheridan (around May 8) and last in Laramie (around May 20). Apply when soil reaches 50°F, before it stays above 55°F.

When is the best time to seed grass in Wyoming?

Early fall is best for cool-season grass (tall fescue, Kentucky bluegrass, perennial ryegrass): typically from Jul 10 to Sep 10 across Wyoming, while soil cools from 65°F toward 50°F.

What type of grass grows in Wyoming?

Most lawns in Wyoming are cool-season grass (tall fescue, Kentucky bluegrass, perennial ryegrass).

Lawn care guides

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