Webster, WI frost dates
How Webster compares
- In 8 years out of 10, the last spring frost in Webster falls between April 28 and May 28, a 30-day window. The first fall frost falls between September 15 and October 13.
- The median last frost is 6 days later than the Wisconsin median of May 5.
- Its 142-day growing season is longer than 18% of the 749 Wisconsin places with a regular frost season (state median 155 days).
- The last frost is typical for zone 4a, where the median is May 12.
- The weather station records an average of 174 nights a year at or below 32°F.
- Compared with Duluth, MN, 103 km away, the last frost here is 3 days earlier than there and the growing season is 9 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 28 |
| 50% (median) | May 11 |
| 10% (safe for tender plants) | May 28 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 15 |
| 50% (median) | September 30 |
| 90% (late) | October 13 |
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 Webster, WI
Webster, WI frost dates — last frost May 11, first frost Sep 30, zone 4a. whenisthelastfrost.com
When to plant vegetables in Webster, WI
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 16 – Mar 2 | Apr 13 – Apr 27 | — | — |
| Peppers | Mar 2 – Mar 16 | May 25 – Jun 8 | — | — |
| Eggplant | Mar 2 – Mar 16 | May 25 – Jun 8 | — | — |
| Tomatoes | Mar 16 – Mar 30 | May 18 – Jun 1 | — | — |
| Lettuce | Mar 16 – Mar 30 | Apr 20 – May 4 | Apr 13 – May 18 | Aug 5 – Sep 2 |
| Kale | Mar 16 – Mar 30 | Apr 13 – Apr 27 | Apr 13 – Apr 27 | Jul 22 – Aug 12 |
| Broccoli | Mar 16 – Mar 30 | Apr 27 – May 11 | — | Jun 24 – Jul 15 |
| Cabbage | Mar 16 – Mar 30 | Apr 20 – May 4 | — | Jun 24 – Jul 15 |
| Cauliflower | Mar 16 – Mar 30 | Apr 27 – May 11 | — | Jun 24 – Jul 15 |
| Okra | Mar 30 – Apr 13 | Jun 1 – Jun 15 | Jun 1 – Jun 15 | — |
| Basil | Mar 30 – Apr 13 | May 18 – Jun 1 | — | — |
| Peas | — | — | Mar 30 – Apr 20 | Jul 8 – Jul 29 |
| Spinach | — | — | Mar 30 – Apr 20 | Aug 5 – Aug 26 |
| Radishes | — | — | Apr 6 – May 18 | Aug 19 – Sep 9 |
| Cucumbers | Apr 13 – Apr 20 | May 25 – Jun 1 | May 18 – Jun 1 | Jul 15 – Jul 29 |
| Zucchini & Summer Squash | Apr 13 – Apr 20 | — | May 18 – Jun 1 | Jul 22 – Aug 5 |
| Winter Squash & Pumpkins | Apr 13 – Apr 20 | — | May 18 – Jun 1 | — |
| Melons & Watermelon | Apr 13 – Apr 20 | May 25 – Jun 8 | — | — |
| Carrots | — | — | Apr 20 – May 18 | Jul 8 – Jul 22 |
| Beets | — | — | Apr 20 – May 18 | Jul 22 – Aug 5 |
| Potatoes | — | — | Apr 20 – May 11 | — |
| Swiss Chard | — | — | Apr 27 – May 25 | Jul 22 – Aug 5 |
| Cilantro | — | — | Apr 27 – May 18 | Aug 5 – Aug 26 |
| Green Beans | — | — | May 18 – Jun 8 | Jul 15 – Jul 29 |
| Sweet Corn | — | — | May 18 – Jun 1 | — |
| Sweet Potatoes | — | May 25 – Jun 15 | — | — |
| Garlic | — | — | — | Sep 16 – Oct 21 |
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 Danbury, WI weather station, 15 km away (elevation 951 ft (290 m)).
Frost dates near Webster
- Danbury May 11 · Sep 30
- Siren May 11 · Oct 1
- Hertel May 14 · Sep 28
- Frederic May 6 · Oct 4
- Grantsburg May 11 · Oct 1
- Shell Lake May 14 · Sep 28
- Spooner May 14 · Sep 28
- Luck May 6 · Oct 4
- Barronett May 5 · Oct 4
- Trego May 10 · Oct 4
Frequently asked questions
When is the last frost in Webster, WI?
The median last spring frost in Webster, WI is May 11. There is still about a 10% chance of frost after May 28, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Webster, WI?
The median first fall frost is September 30, with about a 10% chance of frost before September 15.
How long is the growing season in Webster, WI?
About 142 days between the median last spring frost and first fall frost.
What planting zone is Webster, WI?
Webster, WI is in USDA hardiness zone 4a.