Grayslake, IL frost dates
Last spring frostApr 24median date
First fall frostOct 23median date
Growing season182 daysfrost-free
Hardiness zone5bZone 5b
How Grayslake compares
- In 8 years out of 10, the last spring frost in Grayslake falls between April 11 and May 9, a 28-day window. The first fall frost falls between October 8 and November 4.
- The median last frost is 7 days later than the Illinois median of Apr 17.
- Its 182-day growing season is longer than 37% of the 1,287 Illinois places with a regular frost season (state median 187 days).
- The last frost is 7 days earlier than the zone 5b median of May 1. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 5b chart.
- The weather station records an average of 132 nights a year at or below 32°F.
- Compared with Waukegan, IL, 17 km away, the last frost here is 6 days earlier than there and the growing season is 10 days longer.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 11 |
| 50% (median) | April 24 |
| 10% (safe for tender plants) | May 9 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 8 |
| 50% (median) | October 23 |
| 90% (late) | November 4 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Grayslake, IL
Grayslake, IL frost dates — last frost Apr 24, first frost Oct 23, zone 5b. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Jan 30 to Feb 13Transplant outside: Mar 27 to Apr 10
Start indoors: Feb 13 to Feb 27Transplant outside: May 8 to May 22
Start indoors: Feb 13 to Feb 27Transplant outside: May 8 to May 22
Start indoors: Feb 27 to Mar 13Transplant outside: May 1 to May 15
Start indoors: Feb 27 to Mar 13Transplant outside: Apr 3 to Apr 17Sow outdoors: Mar 27 to May 1Plant for fall: Aug 28 to Sep 25
Start indoors: Feb 27 to Mar 13Transplant outside: Mar 27 to Apr 10Sow outdoors: Mar 27 to Apr 10Plant for fall: Aug 14 to Sep 4
Start indoors: Feb 27 to Mar 13Transplant outside: Apr 10 to Apr 24Plant for fall: Jul 17 to Aug 7
Start indoors: Feb 27 to Mar 13Transplant outside: Apr 3 to Apr 17Plant for fall: Jul 17 to Aug 7
Start indoors: Feb 27 to Mar 13Transplant outside: Apr 10 to Apr 24Plant for fall: Jul 17 to Aug 7
Start indoors: Mar 13 to Mar 27Transplant outside: May 15 to May 29Sow outdoors: May 15 to May 29
Start indoors: Mar 13 to Mar 27Transplant outside: May 1 to May 15
Sow outdoors: Mar 13 to Apr 3Plant for fall: Jul 31 to Aug 21
Sow outdoors: Mar 13 to Apr 3Plant for fall: Aug 28 to Sep 18
Sow outdoors: Mar 20 to May 1Plant for fall: Sep 11 to Oct 2
Start indoors: Mar 27 to Apr 3Transplant outside: May 8 to May 15Sow outdoors: May 1 to May 15Plant for fall: Aug 7 to Aug 21
Start indoors: Mar 27 to Apr 3Sow outdoors: May 1 to May 15Plant for fall: Aug 14 to Aug 28
Start indoors: Mar 27 to Apr 3Sow outdoors: May 1 to May 15
Start indoors: Mar 27 to Apr 3Transplant outside: May 8 to May 22
Sow outdoors: Apr 3 to May 1Plant for fall: Jul 31 to Aug 14
Sow outdoors: Apr 3 to May 1Plant for fall: Aug 14 to Aug 28
Sow outdoors: Apr 3 to Apr 24
Sow outdoors: Apr 10 to May 8Plant for fall: Aug 14 to Aug 28
Sow outdoors: Apr 10 to May 1Plant for fall: Aug 28 to Sep 18
Sow outdoors: May 1 to May 22Plant for fall: Aug 7 to Aug 21
Sow outdoors: May 1 to May 15
Transplant outside: May 8 to May 29
Plant for fall: Oct 9 to Nov 13
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Grayslake, IL
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 30 – Feb 13 | Mar 27 – Apr 10 | — | — |
| Peppers | Feb 13 – Feb 27 | May 8 – May 22 | — | — |
| Eggplant | Feb 13 – Feb 27 | May 8 – May 22 | — | — |
| Tomatoes | Feb 27 – Mar 13 | May 1 – May 15 | — | — |
| Lettuce | Feb 27 – Mar 13 | Apr 3 – Apr 17 | Mar 27 – May 1 | Aug 28 – Sep 25 |
| Kale | Feb 27 – Mar 13 | Mar 27 – Apr 10 | Mar 27 – Apr 10 | Aug 14 – Sep 4 |
| Broccoli | Feb 27 – Mar 13 | Apr 10 – Apr 24 | — | Jul 17 – Aug 7 |
| Cabbage | Feb 27 – Mar 13 | Apr 3 – Apr 17 | — | Jul 17 – Aug 7 |
| Cauliflower | Feb 27 – Mar 13 | Apr 10 – Apr 24 | — | Jul 17 – Aug 7 |
| Okra | Mar 13 – Mar 27 | May 15 – May 29 | May 15 – May 29 | — |
| Basil | Mar 13 – Mar 27 | May 1 – May 15 | — | — |
| Peas | — | — | Mar 13 – Apr 3 | Jul 31 – Aug 21 |
| Spinach | — | — | Mar 13 – Apr 3 | Aug 28 – Sep 18 |
| Radishes | — | — | Mar 20 – May 1 | Sep 11 – Oct 2 |
| Cucumbers | Mar 27 – Apr 3 | May 8 – May 15 | May 1 – May 15 | Aug 7 – Aug 21 |
| Zucchini & Summer Squash | Mar 27 – Apr 3 | — | May 1 – May 15 | Aug 14 – Aug 28 |
| Winter Squash & Pumpkins | Mar 27 – Apr 3 | — | May 1 – May 15 | — |
| Melons & Watermelon | Mar 27 – Apr 3 | May 8 – May 22 | — | — |
| Carrots | — | — | Apr 3 – May 1 | Jul 31 – Aug 14 |
| Beets | — | — | Apr 3 – May 1 | Aug 14 – Aug 28 |
| Potatoes | — | — | Apr 3 – Apr 24 | — |
| Swiss Chard | — | — | Apr 10 – May 8 | Aug 14 – Aug 28 |
| Cilantro | — | — | Apr 10 – May 1 | Aug 28 – Sep 18 |
| Green Beans | — | — | May 1 – May 22 | Aug 7 – Aug 21 |
| Sweet Corn | — | — | May 1 – May 15 | — |
| Sweet Potatoes | — | May 8 – May 29 | — | — |
| Garlic | — | — | — | Oct 9 – Nov 13 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Lake Villa 2ne, IL weather station, 9 km away (elevation 840 ft (256 m)).
Frost dates near Grayslake
- Round Lake Apr 24 · Oct 23
- Lake Villa Apr 24 · Oct 23
- Ingleside May 1 · Oct 11
- Gurnee Apr 30 · Oct 19
- Fox Lake Apr 24 · Oct 23
- Mundelein Apr 29 · Oct 20
- Libertyville Apr 30 · Oct 19
- Wauconda Apr 29 · Oct 20
- Antioch Apr 23 · Oct 21
- Island Lake May 1 · Oct 11
Frequently asked questions
When is the last frost in Grayslake, IL?
The median last spring frost in Grayslake, IL is April 24. There is still about a 10% chance of frost after May 9, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Grayslake, IL?
The median first fall frost is October 23, with about a 10% chance of frost before October 8.
How long is the growing season in Grayslake, IL?
About 182 days between the median last spring frost and first fall frost.
What planting zone is Grayslake, IL?
Grayslake, IL is in USDA hardiness zone 5b.