Girdwood, AK frost dates
Last spring frostMay 8median date
First fall frostSep 29median date
Growing season144 daysfrost-free
Hardiness zone5bZone 5b
How Girdwood compares
- In 8 years out of 10, the last spring frost in Girdwood falls between April 26 and May 22, a 26-day window. The first fall frost falls between September 14 and October 13.
- The median last frost is 13 days earlier than the Alaska median of May 21.
- Its 144-day growing season is longer than 73% of the 165 Alaska places with a regular frost season (state median 124 days).
- The last frost is 7 days later than the zone 5b median of May 1. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 5b chart.
- The weather station records an average of 175 nights a year at or below 32°F.
- Compared with Anchorage, AK, 45 km away, the last frost here is 20 days earlier than there and the growing season is 37 days longer.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 26 |
| 50% (median) | May 8 |
| 10% (safe for tender plants) | May 22 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 14 |
| 50% (median) | September 29 |
| 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 Girdwood, AK
Girdwood, AK frost dates — last frost May 8, first frost Sep 29, zone 5b. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Feb 13 to Feb 27Transplant outside: Apr 10 to Apr 24
Start indoors: Feb 27 to Mar 13Transplant outside: May 22 to Jun 5
Start indoors: Feb 27 to Mar 13Transplant outside: May 22 to Jun 5
Start indoors: Mar 13 to Mar 27Transplant outside: May 15 to May 29
Start indoors: Mar 13 to Mar 27Transplant outside: Apr 17 to May 1Sow outdoors: Apr 10 to May 15Plant for fall: Aug 4 to Sep 1
Start indoors: Mar 13 to Mar 27Transplant outside: Apr 10 to Apr 24Sow outdoors: Apr 10 to Apr 24Plant for fall: Jul 21 to Aug 11
Start indoors: Mar 13 to Mar 27Transplant outside: Apr 24 to May 8Plant for fall: Jun 23 to Jul 14
Start indoors: Mar 13 to Mar 27Transplant outside: Apr 17 to May 1Plant for fall: Jun 23 to Jul 14
Start indoors: Mar 13 to Mar 27Transplant outside: Apr 24 to May 8Plant for fall: Jun 23 to Jul 14
Start indoors: Mar 27 to Apr 10Transplant outside: May 29 to Jun 12Sow outdoors: May 29 to Jun 12
Start indoors: Mar 27 to Apr 10Transplant outside: May 15 to May 29
Sow outdoors: Mar 27 to Apr 17Plant for fall: Jul 7 to Jul 28
Sow outdoors: Mar 27 to Apr 17Plant for fall: Aug 4 to Aug 25
Sow outdoors: Apr 3 to May 15Plant for fall: Aug 18 to Sep 8
Start indoors: Apr 10 to Apr 17Transplant outside: May 22 to May 29Sow outdoors: May 15 to May 29Plant for fall: Jul 14 to Jul 28
Start indoors: Apr 10 to Apr 17Sow outdoors: May 15 to May 29Plant for fall: Jul 21 to Aug 4
Start indoors: Apr 10 to Apr 17Sow outdoors: May 15 to May 29
Start indoors: Apr 10 to Apr 17Transplant outside: May 22 to Jun 5
Sow outdoors: Apr 17 to May 15Plant for fall: Jul 7 to Jul 21
Sow outdoors: Apr 17 to May 15Plant for fall: Jul 21 to Aug 4
Sow outdoors: Apr 17 to May 8
Sow outdoors: Apr 24 to May 22Plant for fall: Jul 21 to Aug 4
Sow outdoors: Apr 24 to May 15Plant for fall: Aug 4 to Aug 25
Sow outdoors: May 15 to Jun 5Plant for fall: Jul 14 to Jul 28
Sow outdoors: May 15 to May 29
Transplant outside: May 22 to Jun 12
Plant for fall: Sep 15 to Oct 20
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Girdwood, AK
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 13 – Feb 27 | Apr 10 – Apr 24 | — | — |
| Peppers | Feb 27 – Mar 13 | May 22 – Jun 5 | — | — |
| Eggplant | Feb 27 – Mar 13 | May 22 – Jun 5 | — | — |
| Tomatoes | Mar 13 – Mar 27 | May 15 – May 29 | — | — |
| Lettuce | Mar 13 – Mar 27 | Apr 17 – May 1 | Apr 10 – May 15 | Aug 4 – Sep 1 |
| Kale | Mar 13 – Mar 27 | Apr 10 – Apr 24 | Apr 10 – Apr 24 | Jul 21 – Aug 11 |
| Broccoli | Mar 13 – Mar 27 | Apr 24 – May 8 | — | Jun 23 – Jul 14 |
| Cabbage | Mar 13 – Mar 27 | Apr 17 – May 1 | — | Jun 23 – Jul 14 |
| Cauliflower | Mar 13 – Mar 27 | Apr 24 – May 8 | — | Jun 23 – Jul 14 |
| Okra | Mar 27 – Apr 10 | May 29 – Jun 12 | May 29 – Jun 12 | — |
| Basil | Mar 27 – Apr 10 | May 15 – May 29 | — | — |
| Peas | — | — | Mar 27 – Apr 17 | Jul 7 – Jul 28 |
| Spinach | — | — | Mar 27 – Apr 17 | Aug 4 – Aug 25 |
| Radishes | — | — | Apr 3 – May 15 | Aug 18 – Sep 8 |
| Cucumbers | Apr 10 – Apr 17 | May 22 – May 29 | May 15 – May 29 | Jul 14 – Jul 28 |
| Zucchini & Summer Squash | Apr 10 – Apr 17 | — | May 15 – May 29 | Jul 21 – Aug 4 |
| Winter Squash & Pumpkins | Apr 10 – Apr 17 | — | May 15 – May 29 | — |
| Melons & Watermelon | Apr 10 – Apr 17 | May 22 – Jun 5 | — | — |
| Carrots | — | — | Apr 17 – May 15 | Jul 7 – Jul 21 |
| Beets | — | — | Apr 17 – May 15 | Jul 21 – Aug 4 |
| Potatoes | — | — | Apr 17 – May 8 | — |
| Swiss Chard | — | — | Apr 24 – May 22 | Jul 21 – Aug 4 |
| Cilantro | — | — | Apr 24 – May 15 | Aug 4 – Aug 25 |
| Green Beans | — | — | May 15 – Jun 5 | Jul 14 – Jul 28 |
| Sweet Corn | — | — | May 15 – May 29 | — |
| Sweet Potatoes | — | May 22 – Jun 12 | — | — |
| Garlic | — | — | — | Sep 15 – Oct 20 |
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 Alyeska, AK weather station, 2 km away (elevation 272 ft (83 m)).
Frost dates near Girdwood
- Hope May 18 · Sep 24
- Indian May 18 · Sep 23
- Whittier Apr 25 · Oct 14
- Moose Pass May 31 · Sep 8
- Eagle River May 9 · Sep 26
- Anchorage May 28 · Sep 12
- Chugiak May 18 · Sep 20
- Cooper Landing Jun 12 · Sep 1
- Wasilla May 16 · Sep 23
- Palmer May 22 · Sep 16
Frequently asked questions
When is the last frost in Girdwood, AK?
The median last spring frost in Girdwood, AK is May 8. There is still about a 10% chance of frost after May 22, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Girdwood, AK?
The median first fall frost is September 29, with about a 10% chance of frost before September 14.
How long is the growing season in Girdwood, AK?
About 144 days between the median last spring frost and first fall frost.
What planting zone is Girdwood, AK?
Girdwood, AK is in USDA hardiness zone 5b.