Frost Dates for Olympia, WA

In Olympia, WA, the average last spring frost is around Apr 29 and the average first fall frost around Oct 14, for a growing season of about 169 days. For frost-tender plants, wait until May 15, when the chance of frost drops to 10%.

Average last frostApr 2950% chance of frost after this date
Safe to plantMay 15only a 10% chance of frost after
Average first frostOct 1450% chance of frost before this date
Growing season169 daysfrost-free in an average year

Based on NOAA 1991–2020 records from the Olympia Airport, WA weather station, 5 miles away, elevation 188 ft. Frost can come earlier in low spots and valleys and later near cities and large lakes.

Frost probability by date

Chance of a 32°F frost after the spring date, or before the fall date.

ChanceLast spring frostFirst fall frost
10%May 15Sep 28
20%May 9Oct 3
30%May 5Oct 6
40%May 2Oct 10
50%Apr 29Oct 14
60%Apr 27Oct 18
70%Apr 23Oct 21
80%Apr 18Oct 26
90%Apr 11Nov 1

Light frost vs. hard freeze

Average (50%) dates for each temperature. Tender plants are damaged at 36°F; most hardy crops survive until 28°F.

TemperatureLast in springFirst in fall
Light frost (36°F)May 15Sep 28
Frost / freeze (32°F)Apr 29Oct 14
Hard freeze (28°F)Apr 5Nov 1

Planting calendar for Olympia

Start indoors Plant outside Fall planting
JanFebMarAprMayJunJulAugSepOctNovDec
Tomatoes
Indoors Mar 4 – Mar 18
Transplant May 6 – May 20
Peppers
Indoors Feb 18 – Mar 4
Transplant May 13 – May 27
Eggplant
Indoors Feb 18 – Mar 4
Transplant May 13 – May 27
Basil
Indoors Mar 18 – Apr 1
Transplant May 6 – May 20
Cucumbers
Indoors Apr 1 – Apr 8
Sow or transplant May 6 – May 20
Zucchini and summer squash
Indoors Apr 1 – Apr 8
Sow or transplant May 6 – May 20
Pumpkins and winter squash
Sow May 6 – May 20
Watermelons and melons
Indoors Apr 1 – Apr 8
Sow or transplant May 13 – May 27
Green beans
Sow May 6 – May 20
Sweet corn
Sow May 6 – May 20
Lettuce
Indoors Mar 18 – Apr 1
Sow or transplant Apr 1 – Apr 15
Fall sowing Aug 19 – Sep 16
Spinach
Sow Mar 18 – Apr 8
Fall sowing Aug 19 – Sep 9
Peas
Sow Mar 18 – Apr 1
Fall sowing Aug 5 – Aug 19
Kale
Indoors Mar 4 – Mar 18
Sow or transplant Apr 1 – Apr 15
Fall sowing Aug 5 – Sep 2
Broccoli
Indoors Mar 4 – Mar 18
Transplant Apr 15 – Apr 29
Fall sowing Jul 22 – Aug 5
Cabbage
Indoors Mar 4 – Mar 18
Transplant Apr 8 – Apr 22
Fall sowing Jul 22 – Aug 5
Carrots
Sow Apr 8 – Apr 29
Fall sowing Jul 22 – Aug 5
Radishes
Sow Mar 25 – Apr 15
Fall sowing Sep 2 – Sep 23
Beets
Sow Apr 8 – Apr 29
Fall sowing Aug 5 – Aug 19
Onions (sets or transplants)
Indoors Feb 4 – Feb 18
Plant Apr 1 – Apr 15
Potatoes
Plant Apr 8 – Apr 22
Garlic
Plant Oct 14 – Nov 11

Based on the average last frost (Apr 29) and first frost (Oct 14). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.

Nearby cities

TumwaterLaceyLakewoodUniversity PlaceTacomaPuyallupFederal WayBremertonAll Washington towns