Watson, IL frost dates
Last spring frostApr 13median date
First fall frostOct 24median date
Growing season194 daysfrost-free
Hardiness zone6bZone 6b
How Watson compares
- In 8 years out of 10, the last spring frost in Watson falls between April 1 and April 29, a 28-day window. The first fall frost falls between October 9 and November 5.
- The median last frost is 4 days earlier than the Illinois median of Apr 17.
- Its 194-day growing season is longer than 74% of the 1,287 Illinois places with a regular frost season (state median 187 days).
- The last frost is 9 days earlier than the zone 6b median of Apr 22. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 6b chart.
- The weather station records an average of 114 nights a year at or below 32°F.
- Compared with Decatur, IL, 102 km away, the last frost here is 1 day earlier than there and the growing season is 1 day longer.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 1 |
| 50% (median) | April 13 |
| 10% (safe for tender plants) | April 29 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 9 |
| 50% (median) | October 24 |
| 90% (late) | November 5 |
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 Watson, IL
Watson, IL frost dates — last frost Apr 13, first frost Oct 24, zone 6b. whenisthelastfrost.com
Crop
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Start indoors: Jan 19 to Feb 2Transplant outside: Mar 16 to Mar 30
Start indoors: Feb 2 to Feb 16Transplant outside: Apr 27 to May 11
Start indoors: Feb 2 to Feb 16Transplant outside: Apr 27 to May 11
Start indoors: Feb 16 to Mar 2Transplant outside: Apr 20 to May 4
Start indoors: Feb 16 to Mar 2Transplant outside: Mar 23 to Apr 6Sow outdoors: Mar 16 to Apr 20Plant for fall: Aug 29 to Sep 26
Start indoors: Feb 16 to Mar 2Transplant outside: Mar 16 to Mar 30Sow outdoors: Mar 16 to Mar 30Plant for fall: Aug 15 to Sep 5
Start indoors: Feb 16 to Mar 2Transplant outside: Mar 30 to Apr 13Plant for fall: Jul 18 to Aug 8
Start indoors: Feb 16 to Mar 2Transplant outside: Mar 23 to Apr 6Plant for fall: Jul 18 to Aug 8
Start indoors: Feb 16 to Mar 2Transplant outside: Mar 30 to Apr 13Plant for fall: Jul 18 to Aug 8
Start indoors: Mar 2 to Mar 16Transplant outside: May 4 to May 18Sow outdoors: May 4 to May 18
Start indoors: Mar 2 to Mar 16Transplant outside: Apr 20 to May 4
Sow outdoors: Mar 2 to Mar 23Plant for fall: Aug 1 to Aug 22
Sow outdoors: Mar 2 to Mar 23Plant for fall: Aug 29 to Sep 19
Sow outdoors: Mar 9 to Apr 20Plant for fall: Sep 12 to Oct 3
Start indoors: Mar 16 to Mar 23Transplant outside: Apr 27 to May 4Sow outdoors: Apr 20 to May 4Plant for fall: Aug 8 to Aug 22
Start indoors: Mar 16 to Mar 23Sow outdoors: Apr 20 to May 4Plant for fall: Aug 15 to Aug 29
Start indoors: Mar 16 to Mar 23Sow outdoors: Apr 20 to May 4
Start indoors: Mar 16 to Mar 23Transplant outside: Apr 27 to May 11
Sow outdoors: Mar 23 to Apr 20Plant for fall: Aug 1 to Aug 15
Sow outdoors: Mar 23 to Apr 20Plant for fall: Aug 15 to Aug 29
Sow outdoors: Mar 23 to Apr 13
Sow outdoors: Mar 30 to Apr 27Plant for fall: Aug 15 to Aug 29
Sow outdoors: Mar 30 to Apr 20Plant for fall: Aug 29 to Sep 19
Sow outdoors: Apr 20 to May 11Plant for fall: Aug 8 to Aug 22
Sow outdoors: Apr 20 to May 4
Transplant outside: Apr 27 to May 18
Plant for fall: Oct 10 to Nov 14
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Watson, IL
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 19 – Feb 2 | Mar 16 – Mar 30 | — | — |
| Peppers | Feb 2 – Feb 16 | Apr 27 – May 11 | — | — |
| Eggplant | Feb 2 – Feb 16 | Apr 27 – May 11 | — | — |
| Tomatoes | Feb 16 – Mar 2 | Apr 20 – May 4 | — | — |
| Lettuce | Feb 16 – Mar 2 | Mar 23 – Apr 6 | Mar 16 – Apr 20 | Aug 29 – Sep 26 |
| Kale | Feb 16 – Mar 2 | Mar 16 – Mar 30 | Mar 16 – Mar 30 | Aug 15 – Sep 5 |
| Broccoli | Feb 16 – Mar 2 | Mar 30 – Apr 13 | — | Jul 18 – Aug 8 |
| Cabbage | Feb 16 – Mar 2 | Mar 23 – Apr 6 | — | Jul 18 – Aug 8 |
| Cauliflower | Feb 16 – Mar 2 | Mar 30 – Apr 13 | — | Jul 18 – Aug 8 |
| Okra | Mar 2 – Mar 16 | May 4 – May 18 | May 4 – May 18 | — |
| Basil | Mar 2 – Mar 16 | Apr 20 – May 4 | — | — |
| Peas | — | — | Mar 2 – Mar 23 | Aug 1 – Aug 22 |
| Spinach | — | — | Mar 2 – Mar 23 | Aug 29 – Sep 19 |
| Radishes | — | — | Mar 9 – Apr 20 | Sep 12 – Oct 3 |
| Cucumbers | Mar 16 – Mar 23 | Apr 27 – May 4 | Apr 20 – May 4 | Aug 8 – Aug 22 |
| Zucchini & Summer Squash | Mar 16 – Mar 23 | — | Apr 20 – May 4 | Aug 15 – Aug 29 |
| Winter Squash & Pumpkins | Mar 16 – Mar 23 | — | Apr 20 – May 4 | — |
| Melons & Watermelon | Mar 16 – Mar 23 | Apr 27 – May 11 | — | — |
| Carrots | — | — | Mar 23 – Apr 20 | Aug 1 – Aug 15 |
| Beets | — | — | Mar 23 – Apr 20 | Aug 15 – Aug 29 |
| Potatoes | — | — | Mar 23 – Apr 13 | — |
| Swiss Chard | — | — | Mar 30 – Apr 27 | Aug 15 – Aug 29 |
| Cilantro | — | — | Mar 30 – Apr 20 | Aug 29 – Sep 19 |
| Green Beans | — | — | Apr 20 – May 11 | Aug 8 – Aug 22 |
| Sweet Corn | — | — | Apr 20 – May 4 | — |
| Sweet Potatoes | — | Apr 27 – May 18 | — | — |
| Garlic | — | — | — | Oct 10 – Nov 14 |
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 Effingham 3sw, IL weather station, 15 km away (elevation 627 ft (191 m)).
Frost dates near Watson
- Mason Apr 13 · Oct 24
- Edgewood Apr 10 · Oct 23
- Dieterich Apr 13 · Oct 22
- Effingham Apr 13 · Oct 24
- Teutopolis Apr 13 · Oct 24
- Altamont Apr 13 · Oct 24
- Wheeler Apr 13 · Oct 22
- Shumway Apr 13 · Oct 24
- Farina Apr 3 · Oct 24
- Louisville Apr 10 · Oct 23
Frequently asked questions
When is the last frost in Watson, IL?
The median last spring frost in Watson, IL is April 13. There is still about a 10% chance of frost after April 29, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Watson, IL?
The median first fall frost is October 24, with about a 10% chance of frost before October 9.
How long is the growing season in Watson, IL?
About 194 days between the median last spring frost and first fall frost.
What planting zone is Watson, IL?
Watson, IL is in USDA hardiness zone 6b.