Macomb, IL frost dates
Last spring frostApr 17median date
First fall frostOct 22median date
Growing season188 daysfrost-free
Hardiness zone6aZone 6a
How Macomb compares
- In 8 years out of 10, the last spring frost in Macomb falls between April 4 and May 2, a 28-day window. The first fall frost falls between October 7 and November 1.
- The median last frost is the same as the Illinois median of Apr 17.
- Its 188-day growing season is longer than 51% of the 1,287 Illinois places with a regular frost season (state median 187 days).
- The last frost is 12 days earlier than the zone 6a median of Apr 29. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 6a chart.
- The weather station records an average of 127 nights a year at or below 32°F.
- Compared with Peoria, IL, 92 km away, the last frost here is 1 day later than there and the growing season is 2 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 4 |
| 50% (median) | April 17 |
| 10% (safe for tender plants) | May 2 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 7 |
| 50% (median) | October 22 |
| 90% (late) | November 1 |
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 Macomb, IL
Macomb, IL frost dates — last frost Apr 17, first frost Oct 22, zone 6a. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Jan 23 to Feb 6Transplant outside: Mar 20 to Apr 3
Start indoors: Feb 6 to Feb 20Transplant outside: May 1 to May 15
Start indoors: Feb 6 to Feb 20Transplant outside: May 1 to May 15
Start indoors: Feb 20 to Mar 6Transplant outside: Apr 24 to May 8
Start indoors: Feb 20 to Mar 6Transplant outside: Mar 27 to Apr 10Sow outdoors: Mar 20 to Apr 24Plant for fall: Aug 27 to Sep 24
Start indoors: Feb 20 to Mar 6Transplant outside: Mar 20 to Apr 3Sow outdoors: Mar 20 to Apr 3Plant for fall: Aug 13 to Sep 3
Start indoors: Feb 20 to Mar 6Transplant outside: Apr 3 to Apr 17Plant for fall: Jul 16 to Aug 6
Start indoors: Feb 20 to Mar 6Transplant outside: Mar 27 to Apr 10Plant for fall: Jul 16 to Aug 6
Start indoors: Feb 20 to Mar 6Transplant outside: Apr 3 to Apr 17Plant for fall: Jul 16 to Aug 6
Start indoors: Mar 6 to Mar 20Transplant outside: May 8 to May 22Sow outdoors: May 8 to May 22
Start indoors: Mar 6 to Mar 20Transplant outside: Apr 24 to May 8
Sow outdoors: Mar 6 to Mar 27Plant for fall: Jul 30 to Aug 20
Sow outdoors: Mar 6 to Mar 27Plant for fall: Aug 27 to Sep 17
Sow outdoors: Mar 13 to Apr 24Plant for fall: Sep 10 to Oct 1
Start indoors: Mar 20 to Mar 27Transplant outside: May 1 to May 8Sow outdoors: Apr 24 to May 8Plant for fall: Aug 6 to Aug 20
Start indoors: Mar 20 to Mar 27Sow outdoors: Apr 24 to May 8Plant for fall: Aug 13 to Aug 27
Start indoors: Mar 20 to Mar 27Sow outdoors: Apr 24 to May 8
Start indoors: Mar 20 to Mar 27Transplant outside: May 1 to May 15
Sow outdoors: Mar 27 to Apr 24Plant for fall: Jul 30 to Aug 13
Sow outdoors: Mar 27 to Apr 24Plant for fall: Aug 13 to Aug 27
Sow outdoors: Mar 27 to Apr 17
Sow outdoors: Apr 3 to May 1Plant for fall: Aug 13 to Aug 27
Sow outdoors: Apr 3 to Apr 24Plant for fall: Aug 27 to Sep 17
Sow outdoors: Apr 24 to May 15Plant for fall: Aug 6 to Aug 20
Sow outdoors: Apr 24 to May 8
Transplant outside: May 1 to May 22
Plant for fall: Oct 8 to Nov 12
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Macomb, IL
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 23 – Feb 6 | Mar 20 – Apr 3 | — | — |
| Peppers | Feb 6 – Feb 20 | May 1 – May 15 | — | — |
| Eggplant | Feb 6 – Feb 20 | May 1 – May 15 | — | — |
| Tomatoes | Feb 20 – Mar 6 | Apr 24 – May 8 | — | — |
| Lettuce | Feb 20 – Mar 6 | Mar 27 – Apr 10 | Mar 20 – Apr 24 | Aug 27 – Sep 24 |
| Kale | Feb 20 – Mar 6 | Mar 20 – Apr 3 | Mar 20 – Apr 3 | Aug 13 – Sep 3 |
| Broccoli | Feb 20 – Mar 6 | Apr 3 – Apr 17 | — | Jul 16 – Aug 6 |
| Cabbage | Feb 20 – Mar 6 | Mar 27 – Apr 10 | — | Jul 16 – Aug 6 |
| Cauliflower | Feb 20 – Mar 6 | Apr 3 – Apr 17 | — | Jul 16 – Aug 6 |
| Okra | Mar 6 – Mar 20 | May 8 – May 22 | May 8 – May 22 | — |
| Basil | Mar 6 – Mar 20 | Apr 24 – May 8 | — | — |
| Peas | — | — | Mar 6 – Mar 27 | Jul 30 – Aug 20 |
| Spinach | — | — | Mar 6 – Mar 27 | Aug 27 – Sep 17 |
| Radishes | — | — | Mar 13 – Apr 24 | Sep 10 – Oct 1 |
| Cucumbers | Mar 20 – Mar 27 | May 1 – May 8 | Apr 24 – May 8 | Aug 6 – Aug 20 |
| Zucchini & Summer Squash | Mar 20 – Mar 27 | — | Apr 24 – May 8 | Aug 13 – Aug 27 |
| Winter Squash & Pumpkins | Mar 20 – Mar 27 | — | Apr 24 – May 8 | — |
| Melons & Watermelon | Mar 20 – Mar 27 | May 1 – May 15 | — | — |
| Carrots | — | — | Mar 27 – Apr 24 | Jul 30 – Aug 13 |
| Beets | — | — | Mar 27 – Apr 24 | Aug 13 – Aug 27 |
| Potatoes | — | — | Mar 27 – Apr 17 | — |
| Swiss Chard | — | — | Apr 3 – May 1 | Aug 13 – Aug 27 |
| Cilantro | — | — | Apr 3 – Apr 24 | Aug 27 – Sep 17 |
| Green Beans | — | — | Apr 24 – May 15 | Aug 6 – Aug 20 |
| Sweet Corn | — | — | Apr 24 – May 8 | — |
| Sweet Potatoes | — | May 1 – May 22 | — | — |
| Garlic | — | — | — | Oct 8 – Nov 12 |
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 Prairie City 2s, IL weather station, 23 km away (elevation 650 ft (198 m)).
Frost dates near Macomb
- Bardolph Apr 17 · Oct 22
- Colchester Apr 21 · Oct 19
- Good Hope Apr 17 · Oct 22
- Sciota Apr 21 · Oct 19
- Tennessee Apr 21 · Oct 19
- Industry Apr 16 · Oct 23
- Adair Apr 17 · Oct 22
- Bushnell Apr 17 · Oct 22
- Blandinsville Apr 21 · Oct 19
- Table Grove Apr 17 · Oct 22
Frequently asked questions
When is the last frost in Macomb, IL?
The median last spring frost in Macomb, IL is April 17. There is still about a 10% chance of frost after May 2, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Macomb, IL?
The median first fall frost is October 22, with about a 10% chance of frost before October 7.
How long is the growing season in Macomb, IL?
About 188 days between the median last spring frost and first fall frost.
What planting zone is Macomb, IL?
Macomb, IL is in USDA hardiness zone 6a.