USDA Hardiness Zone 7b
Frost Dates for 99835 — Sitka, Alaska
Averages from Sitka 1 Ne, Ak US, the nearest reporting station, 0.5 miles away.
Plant tender crops after May 3, and expect the first autumn freeze around October 18. That leaves about 166 frost-free days.
- Last spring frost
- May 3
- First fall frost
- October 18
- Growing season
- 166 days
- Hardiness zone
- 7b
50% probability
50% probability
frost-free
5 to 10°F annual low
Planting calendar for 99835
| When | What to do |
|---|---|
| February 22 – March 8 | Start peppers and aubergines indoors They need eight to ten weeks under lights before they can go out. |
| March 8 – March 22 | Start tomatoes indoors Six to eight weeks gives a transplant big enough to set fruit early. |
| April 5 – April 19 | Sow peas, spinach, lettuce, radish outdoors These tolerate light frost and prefer to germinate in cool soil. |
| May 3 onward | Transplant tomatoes, peppers, basil, squash, cucumbers The average last freeze has passed — still watch the actual forecast. |
| by July 26 | Sow the autumn crop of carrots, beets and brassicas They need about twelve weeks to size up before growth stops. |
| by October 4 | Harvest tender crops, or be ready to cover them A first freeze two weeks early is well within normal variation. |
| October 18 onward | Plant garlic, mulch beds, lift tender bulbs Garlic wants a cold spell; bare soil loses structure over winter. |
What these dates mean
Wait until after May 3 to put tender plants — tomatoes, peppers, basil, squash — in the ground. That is the date by which half of years in Sitka, Alaska are past their last freeze. Harvest before October 18, which leaves roughly 166 frost-free days.
ZIP 99835 sits in USDA hardiness zone 7b, meaning the average coldest night of the year falls between 5 to 10°F. Zone decides what survives the winter; frost dates decide when to plant each spring. They are different questions, and a plant can pass one and fail the other.
These are thirty-year NOAA averages for 1991–2020, not a forecast. Any individual year can frost two to three weeks either side of these dates, so check the actual forecast before planting out.