LawnWeather

Green Bay, WI Lawn Care Calendar

In a typical year, put down crabgrass preventer in Green Bay between May 4 and May 23. The best time to overseed is between Aug 5 and Sep 24. The last spring frost usually comes around May 4. Most lawns here are cool-season grass (tall fescue, Kentucky bluegrass, ryegrass).

Typical lawn care dates in Green Bay

Crabgrass preventer (pre-emergent)
May 4 – May 23
Spring fertilizer
May 16 – Jun 20
Overseeding & seeding
Aug 5 – Sep 24
Fall fertilizer
Jul 22 – Oct 26
Light band: typical frost-free season. Bars: typical windows.
TaskTypical window
Crabgrass preventer (pre-emergent)Crabgrass sprouts once soil stays above 55°F. Apply when soil reaches 50°F, before that happens.May 4 – May 23
Spring fertilizerA light feeding once soil warms past 55°F and the grass is actively growing.May 16 – Jun 20
Overseeding & seedingLate summer to early fall: seedlings need about 6–10 weeks of growth before the first frost.Aug 5 – Sep 24
Fall fertilizerThe most important feeding for cool-season grass, from early fall until soil cools to about 45°F.Jul 22 – Oct 26

Median dates, 2016–2025, from NOAA weather data for Green Bay. This year's dates can differ by a few weeks.

Month-by-month lawn care in Green Bay

  1. JanuaryNo treatments due; mow as needed.
  2. FebruaryNo treatments due; mow as needed.
  3. MarchNo treatments due; mow as needed.
  4. AprilNo treatments due; mow as needed.
  5. MayCrabgrass preventer (pre-emergent)Spring fertilizer
  6. JuneSpring fertilizer
  7. JulyFall fertilizer
  8. AugustOverseeding & seedingFall fertilizer
  9. SeptemberOverseeding & seedingFall fertilizer
  10. OctoberFall fertilizer
  11. NovemberNo treatments due; mow as needed.
  12. DecemberNo treatments due; mow as needed.

Soil temperature in Green Bay by month

Average soil temperature 4 inches down, estimated from 2016–2025 weather. It bottoms out in January at 21°F and peaks in July at 71°F. Crabgrass preventer goes down when it reaches 50°F, usually around May 4.

JanFebMarAprMayJunJulAugSepOctNovDec
21°F21°F32°F42°F54°F66°F71°F69°F63°F51°F38°F26°F

Green Bay lawn timing, year by year

Over the last 10 years, soil in Green Bay reached 50°F, the signal for crabgrass preventer, as early as Apr 7 (2021) and as late as May 20 (2020): 43 days apart. A fixed calendar date can't follow that, which is why the report above uses this year's soil temperature. Between the typical last spring frost (May 4) and first fall frost (Oct 19), the growing season lasts about 168 days.

YearCrabgrass window openedLast spring frostFirst fall frost
2025May 6Apr 16Oct 24
2024Apr 14Apr 25Nov 21
2023Apr 12May 2Oct 30
2022May 10May 5Oct 15
2021Apr 7May 12Oct 22
2020May 20May 13Oct 2
2019May 15Apr 28Oct 14
2018May 2Apr 29Oct 13
2017May 12May 9Oct 29
2016Apr 18May 15Oct 13

Estimated from daily temperatures for Green Bay. A dash means it didn't happen that year.

Frequently asked questions

When should I apply pre-emergent in Green Bay?

In a typical year, between May 4 and May 23. Put it down when soil reaches 50°F, before it stays above 55°F and crabgrass starts sprouting. Early springs move this up by a week or more, so check this year's soil temperature above.

When is the best time to plant grass seed in Green Bay?

Early fall, typically Aug 5 – Sep 24, while soil cools from 65°F toward 50°F.

When is the last frost in Green Bay?

The median last spring frost is May 4 and the median first fall frost is Oct 19 (2016–2025).

How long is the growing season in Green Bay?

About 168 days, from the median last spring frost on May 4 to the median first fall frost on Oct 19 (2016–2025).

Lawn care guides

Growing vegetables too? See the Green Bay planting calendarfor when to start seeds and plant outside.

More Wisconsin lawn calendars

Nearby cities in other states