Frost dates for 06816 — Danbury, CT
Last spring frostApr 20median date
First fall frostOct 20median date
Growing season183 daysfrost-free
Hardiness zone6bZone 6b
How Danbury compares
- In 8 years out of 10, the last spring frost in Danbury falls between April 7 and May 6, a 29-day window. The first fall frost falls between October 5 and November 4.
- The median last frost is 1 day earlier than the Connecticut median of Apr 21.
- Its 183-day growing season is longer than 54% of the 267 Connecticut places with a regular frost season (state median 178 days).
- The last frost is typical for zone 6b, where the median is Apr 22.
- The weather station records an average of 126 nights a year at or below 32°F.
- Compared with Norwalk, CT, 16 km away, the last frost here is 3 days later than there and the growing season is 6 days shorter.
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 5 |
| 50% (median) | October 20 |
| 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 Danbury, CT
Frost dates for 06816 — Danbury, CT — last frost Apr 20, first frost Oct 20, zone 6b. whenisthelastfrost.com
Crop
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Start indoors: Jan 26 to Feb 9Transplant outside: Mar 23 to Apr 6
Start indoors: Feb 9 to Feb 23Transplant outside: May 4 to May 18
Start indoors: Feb 9 to Feb 23Transplant outside: May 4 to May 18
Start indoors: Feb 23 to Mar 9Transplant outside: Apr 27 to May 11
Start indoors: Feb 23 to Mar 9Transplant outside: Mar 30 to Apr 13Sow outdoors: Mar 23 to Apr 27Plant for fall: Aug 25 to Sep 22
Start indoors: Feb 23 to Mar 9Transplant outside: Mar 23 to Apr 6Sow outdoors: Mar 23 to Apr 6Plant for fall: Aug 11 to Sep 1
Start indoors: Feb 23 to Mar 9Transplant outside: Apr 6 to Apr 20Plant for fall: Jul 14 to Aug 4
Start indoors: Feb 23 to Mar 9Transplant outside: Mar 30 to Apr 13Plant for fall: Jul 14 to Aug 4
Start indoors: Feb 23 to Mar 9Transplant outside: Apr 6 to Apr 20Plant for fall: Jul 14 to Aug 4
Start indoors: Mar 9 to Mar 23Transplant outside: May 11 to May 25Sow outdoors: May 11 to May 25
Start indoors: Mar 9 to Mar 23Transplant outside: Apr 27 to May 11
Sow outdoors: Mar 9 to Mar 30Plant for fall: Jul 28 to Aug 18
Sow outdoors: Mar 9 to Mar 30Plant for fall: Aug 25 to Sep 15
Sow outdoors: Mar 16 to Apr 27Plant for fall: Sep 8 to Sep 29
Start indoors: Mar 23 to Mar 30Transplant outside: May 4 to May 11Sow outdoors: Apr 27 to May 11Plant for fall: Aug 4 to Aug 18
Start indoors: Mar 23 to Mar 30Sow outdoors: Apr 27 to May 11Plant for fall: Aug 11 to Aug 25
Start indoors: Mar 23 to Mar 30Sow outdoors: Apr 27 to May 11
Start indoors: Mar 23 to Mar 30Transplant outside: May 4 to May 18
Sow outdoors: Mar 30 to Apr 27Plant for fall: Jul 28 to Aug 11
Sow outdoors: Mar 30 to Apr 27Plant for fall: Aug 11 to Aug 25
Sow outdoors: Mar 30 to Apr 20
Sow outdoors: Apr 6 to May 4Plant for fall: Aug 11 to Aug 25
Sow outdoors: Apr 6 to Apr 27Plant for fall: Aug 25 to Sep 15
Sow outdoors: Apr 27 to May 18Plant for fall: Aug 4 to Aug 18
Sow outdoors: Apr 27 to May 11
Transplant outside: May 4 to May 25
Plant for fall: Oct 6 to Nov 10
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Danbury, CT
| 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 25 – Sep 22 |
| Kale | Feb 23 – Mar 9 | Mar 23 – Apr 6 | Mar 23 – Apr 6 | Aug 11 – Sep 1 |
| Broccoli | Feb 23 – Mar 9 | Apr 6 – Apr 20 | — | Jul 14 – Aug 4 |
| Cabbage | Feb 23 – Mar 9 | Mar 30 – Apr 13 | — | Jul 14 – Aug 4 |
| Cauliflower | Feb 23 – Mar 9 | Apr 6 – Apr 20 | — | Jul 14 – Aug 4 |
| 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 28 – Aug 18 |
| Spinach | — | — | Mar 9 – Mar 30 | Aug 25 – Sep 15 |
| Radishes | — | — | Mar 16 – Apr 27 | Sep 8 – Sep 29 |
| Cucumbers | Mar 23 – Mar 30 | May 4 – May 11 | Apr 27 – May 11 | Aug 4 – Aug 18 |
| Zucchini & Summer Squash | Mar 23 – Mar 30 | — | Apr 27 – May 11 | Aug 11 – Aug 25 |
| 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 28 – Aug 11 |
| Beets | — | — | Mar 30 – Apr 27 | Aug 11 – Aug 25 |
| Potatoes | — | — | Mar 30 – Apr 20 | — |
| Swiss Chard | — | — | Apr 6 – May 4 | Aug 11 – Aug 25 |
| Cilantro | — | — | Apr 6 – Apr 27 | Aug 25 – Sep 15 |
| Green Beans | — | — | Apr 27 – May 18 | Aug 4 – Aug 18 |
| Sweet Corn | — | — | Apr 27 – May 11 | — |
| Sweet Potatoes | — | May 4 – May 25 | — | — |
| Garlic | — | — | — | Oct 6 – Nov 10 |
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, CT weather station, 11 km away (elevation 404 ft (123 m)).
ZIP codes in Danbury: 06810 06811 06813 06814 06816 06817
Frost dates near Danbury
- Redding Center Apr 20 · Oct 20
- Redding Ridge Apr 20 · Oct 20
- Redding May 1 · Oct 14
- Georgetown May 1 · Oct 14
- Bethel Apr 20 · Oct 20
- Easton Apr 5 · Nov 6
- Weston Apr 17 · Oct 23
- Newtown Apr 20 · Oct 20
Frequently asked questions
When is the last frost in Danbury, CT?
The median last spring frost in Danbury, CT 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 Danbury, CT?
The median first fall frost is October 20, with about a 10% chance of frost before October 5.
How long is the growing season in Danbury, CT?
About 183 days between the median last spring frost and first fall frost.
What planting zone is Danbury, CT?
Danbury, CT is in USDA hardiness zone 6b.