Frost dates for 60440 — Bolingbrook, IL
How Bolingbrook compares
- In 8 years out of 10, the last spring frost in Bolingbrook falls between April 7 and May 6, a 29-day window. The first fall frost falls between October 7 and November 3.
- The median last frost is 3 days later than the Illinois median of Apr 17.
- Its 185-day growing season is longer than 44% 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 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 123 nights a year at or below 32°F.
- Compared with Naperville, IL, 9 km away, the last frost here is 8 days earlier than there and the growing season is 14 days longer.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 7 |
| 50% (median) | April 20 |
| 10% (safe for tender plants) | May 6 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 7 |
| 50% (median) | October 22 |
| 90% (late) | November 3 |
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 Bolingbrook, IL
Frost dates for 60440 — Bolingbrook, IL — last frost Apr 20, first frost Oct 22, zone 6a. whenisthelastfrost.com
When to plant vegetables in Bolingbrook, IL
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 26 – Feb 9 | Mar 23 – Apr 6 | — | — |
| Peppers | Feb 9 – Feb 23 | May 4 – May 18 | — | — |
| Eggplant | Feb 9 – Feb 23 | May 4 – May 18 | — | — |
| Tomatoes | Feb 23 – Mar 9 | Apr 27 – May 11 | — | — |
| Lettuce | Feb 23 – Mar 9 | Mar 30 – Apr 13 | Mar 23 – Apr 27 | Aug 27 – Sep 24 |
| Kale | Feb 23 – Mar 9 | Mar 23 – Apr 6 | Mar 23 – Apr 6 | Aug 13 – Sep 3 |
| Broccoli | Feb 23 – Mar 9 | Apr 6 – Apr 20 | — | Jul 16 – Aug 6 |
| Cabbage | Feb 23 – Mar 9 | Mar 30 – Apr 13 | — | Jul 16 – Aug 6 |
| Cauliflower | Feb 23 – Mar 9 | Apr 6 – Apr 20 | — | Jul 16 – Aug 6 |
| Okra | Mar 9 – Mar 23 | May 11 – May 25 | May 11 – May 25 | — |
| Basil | Mar 9 – Mar 23 | Apr 27 – May 11 | — | — |
| Peas | — | — | Mar 9 – Mar 30 | Jul 30 – Aug 20 |
| Spinach | — | — | Mar 9 – Mar 30 | Aug 27 – Sep 17 |
| Radishes | — | — | Mar 16 – Apr 27 | Sep 10 – Oct 1 |
| Cucumbers | Mar 23 – Mar 30 | May 4 – May 11 | Apr 27 – May 11 | Aug 6 – Aug 20 |
| Zucchini & Summer Squash | Mar 23 – Mar 30 | — | Apr 27 – May 11 | Aug 13 – Aug 27 |
| Winter Squash & Pumpkins | Mar 23 – Mar 30 | — | Apr 27 – May 11 | — |
| Melons & Watermelon | Mar 23 – Mar 30 | May 4 – May 18 | — | — |
| Carrots | — | — | Mar 30 – Apr 27 | Jul 30 – Aug 13 |
| Beets | — | — | Mar 30 – Apr 27 | Aug 13 – Aug 27 |
| Potatoes | — | — | Mar 30 – Apr 20 | — |
| Swiss Chard | — | — | Apr 6 – May 4 | Aug 13 – Aug 27 |
| Cilantro | — | — | Apr 6 – Apr 27 | Aug 27 – Sep 17 |
| Green Beans | — | — | Apr 27 – May 18 | Aug 6 – Aug 20 |
| Sweet Corn | — | — | Apr 27 – May 11 | — |
| Sweet Potatoes | — | May 4 – May 25 | — | — |
| 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 Romeoville Wfo, IL weather station, 10 km away (elevation 659 ft (201 m)).
ZIP codes in Bolingbrook: 60440 60490
Frost dates near Bolingbrook
- Romeoville Apr 20 · Oct 22
- Woodridge Apr 28 · Oct 16
- Lemont Apr 19 · Oct 22
- Naperville Apr 28 · Oct 16
- Lisle Apr 28 · Oct 16
- Darien Apr 19 · Oct 22
- Downers Grove Apr 28 · Oct 16
- Lockport Apr 20 · Oct 22
Frequently asked questions
When is the last frost in Bolingbrook, IL?
The median last spring frost in Bolingbrook, IL is April 20. There is still about a 10% chance of frost after May 6, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Bolingbrook, 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 Bolingbrook, IL?
About 185 days between the median last spring frost and first fall frost.
What planting zone is Bolingbrook, IL?
Bolingbrook, IL is in USDA hardiness zone 6a.