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Frost dates and planting calendar for Tacoma, Washington

Updated October 30, 2026. Based on USDA, NOAA and Colorado State University Extension data. Published by Humblebee.

USDA hardiness zone
8b[1]
Median last spring frost
Mar 8[2]
Median first fall frost
Nov 14[3]
Growing season, median
250 days[4]

The center of Tacoma is in USDA hardiness zone 8b[1]. The median last spring frost is March 8, so in half of years the last frost comes after that date[2].

Frost dates

JanFebMarAprMayJunJulAugSepOctNovDecLast spring frost: 9 in 10 years after Feb 15, half of years Mar 8, 1 in 10 years after Mar 31Last frostmedian Mar 8First fall frost: 9 in 10 years before Dec 2, half of years Nov 14, 1 in 10 years before Oct 30First frostmedian Nov 14Frost riskHardyHardy vegetables: plant Feb 8 to Feb 22Feb 8 to Feb 22Semi-hardySemi-hardy vegetables: plant Feb 22 to Mar 8Feb 22 to Mar 8TenderTender vegetables: plant around Mar 8around Mar 8Very tenderVery tender vegetables: plant from Mar 22from Mar 22
Shaded: the span between the dates frost passes in 9 of 10 years and 1 of 10 years[2][3]. Green: planting windows from the CSU rules applied to the median last frost (GardenFacts calculation)[6]. Exact dates are in the tables below.

NOAA frost dates for Tacoma come from the Tacoma #1 weather station, using records from 1991 to 2020[5]. In half of years the last spring frost comes after March 8, and in 1 of 10 years it comes after March 31[2]. In half of years the first fall frost comes before November 14, and in 1 of 10 years it comes before October 30[3]. These are odds from past years, not a forecast, so any year can be earlier or later.

Frost Likely (9 in 10 years) Even odds (5 in 10) Unlikely (1 in 10)
Last spring frost (32°F)[2] after February 15 after March 8 after March 31
First fall frost (32°F)[3] before October 30 before November 14 before December 2
  • Hard freeze (28°F): median last spring date February 11, median first fall date December 1[7].
  • Frost-free growing season: at least 223 days in 9 of 10 years, 250 days in half of years and 283 days in 1 of 10 years[4].
  • The low reached 32°F or colder in 100% of years and 28°F or colder in 98.5% of years[8].
  • Weather station: Tacoma #1 (USC00458278), 2.3 miles from the city center, 25 feet, 26 years of 1991 to 2020 records[5].

When to plant vegetables

Colorado State University Extension wrote its planting guide for Colorado, so these dates are a simple calculation and not local advice[6]. Hardy vegetables such as broccoli, lettuce, peas and spinach can go in as early as 2 to 4 weeks before the median last frost, which is February 8 to February 22[6]. Semi-hardy vegetables such as beets, carrots and potatoes can go in as early as 2 weeks before the median last frost, which is February 22[9]. Tender vegetables such as snap beans and sweet corn can be planted from seed around March 8[10]. Very tender vegetables such as tomatoes and peppers typically start 2 or more weeks after the median last frost, with the earliest start on March 22[11].

  • Hardy (broccoli, cabbage, kohlrabi, lettuce, onions, peas, radishes, spinach, turnips): as early as 2 to 4 weeks before the median last frost (March 8) is February 8 to February 22[6]
  • Semi-hardy (beets, carrots, cauliflower, parsnips, potatoes, Swiss chard): as early as 2 weeks before the median last frost (March 8) is February 22, up to the median date itself[9]
  • Tender (snap beans, sweet corn, cucumbers, summer squash): from seed around the median last frost date, March 8[10]
  • Very tender (cantaloupe, eggplant, peppers, tomatoes, winter squash, watermelon): the earliest start, two weeks after the median last frost (March 8), is March 22[11]
Vegetable (CSU group) Plant from First harvest around
Broccoli (hardy)[12] Feb 8 Apr 14 (from transplants)
Cabbage (hardy)[12] Feb 8 May 4 (from transplants)
Kohlrabi (hardy)[12] Feb 8 Mar 30
Lettuce (hardy)[12] Feb 8 Apr 9
Onions (hardy)[12] Feb 8 May 29
Peas (hardy)[12] Feb 8 Apr 14
Radishes (hardy)[12] Feb 8 Mar 10
Spinach (hardy)[12] Feb 8 Mar 20
Turnips (hardy)[12] Feb 8 Mar 30
Beets (semi-hardy)[12] Feb 22 Apr 23
Carrots (semi-hardy)[12] Feb 22 May 3
Cauliflower (semi-hardy)[12] Feb 22 not listed
Parsnips (semi-hardy)[12] Feb 22 May 3
Potatoes (semi-hardy)[12] Feb 22 Jun 27
Swiss chard (semi-hardy)[12] Feb 22 Apr 23
Snap beans (tender)[12] Mar 8 May 7
Sweet corn (tender)[12] Mar 8 May 7
Cucumbers (tender)[12] Mar 8 May 2
Summer squash (tender)[12] Mar 8 Apr 27
Cantaloupe (very tender)[12] Mar 22 Jun 15
Eggplant (very tender)[12] Mar 22 May 21 (from transplants)
Peppers (very tender)[12] Mar 22 May 31 (from transplants)
Tomatoes (very tender)[12] Mar 22 May 26 (from transplants)
Winter squash (very tender)[12] Mar 22 Jun 30
Watermelon (very tender)[12] Mar 22 Jun 15
Spacing, depth and soil temperature (CSU Extension)
Vegetable Min. soil temp Depth Spacing Days to harvest
Broccoli[13] 40°F 1/2 in 18 in 65
Cabbage[13] 40°F 1/2 in 18 in 85
Kohlrabi[13] 40°F 1/2 in 7-9 in 50
Lettuce[13] 35°F 1/4 in 7-9 in 60
Onions[13] 35°F 1/4 in (seed), 1-2 in (sets) 4-6 in 110
Peas[13] 40°F 1 in 4-6 in 65
Radishes[13] 40°F 1/2 in 2-3 in 30
Spinach[13] 40°F 1/2 in 4-6 in 40
Turnips[13] 40°F 1/2 in 4-6 in 50
Beets[13] 40°F 3/4-1 in 4-6 in 60
Carrots[13] 40°F 1/4 in 2-3 in 70
Cauliflower[13] 40°F 1/2 in 18 in –
Parsnips[13] 35°F 1/2 in 5-6 in 70
Potatoes[13] 45°F – – 125
Swiss chard[13] 40°F 1 in 7-9 in 60
Snap beans[13] 55°F 1-1 1/2 in 6 in 60
Sweet corn[13] 50°F 1-1 1/2 in 12 x 30 in or 9 x 36 in 60-90
Cucumbers[13] 60°F 1 in 6 in trellised, 24-36 in untrellised 55
Summer squash[13] 60°F 1-1 1/2 in 36-48 in 50
Cantaloupe[13] 60°F 1-1 1/2 in 36-48 in 85
Eggplant[13] 60°F 1/4 in 18-24 in 60
Peppers[13] 60°F 1/4 in 15-18 in 70
Tomatoes[13] 50°F 1/4 in 24 in trellised 65
Winter squash[13] 60°F 1-1 1/2 in 36-48 in 100
Watermelon[13] 60°F 1-1 1/2 in 36-48 in 85

Hardiness zone

The USDA map puts the center of Tacoma in zone 8b, which means an average coldest night of 15°F to 20°F over 1991 to 2020[1]. A zone is based on the coldest winter night, not on summer heat or frost dates[14]. Tacoma is not all one zone. By land area, 73% is in ZIP code areas rated 8b and 27% is in areas rated 9a[15].

Zone 8b: average annual extreme minimum temperature 15°F to 20°F (1991 to 2020)[1]. Modeled value at the city center: 18.7°F[1].

Share of the city's land area by ZIP code zone: zone 8b 73%, zone 9a 27%[15].

All towns in zone 8b and what zone 8b means

Zone by ZIP code
ZIP code Zone Coldest night range
98409[15] 8b 15 to 20°F
98421[15] 9a 20 to 25°F
98404[15] 8b 15 to 20°F
98407[15] 9a 20 to 25°F
98422[15] 8b 15 to 20°F
98406[15] 8b 15 to 20°F
98405[15] 8b 15 to 20°F
98408[15] 8b 15 to 20°F
98418[15] 8b 15 to 20°F
98465[15] 9a 20 to 25°F
98444[15] 8b 15 to 20°F
98402[15] 8b 15 to 20°F
98403[15] 8b 15 to 20°F
98466[15] 8b 15 to 20°F
98445[15] 8b 15 to 20°F
98467[15] 8b 15 to 20°F
98424[15] 8b 15 to 20°F
98499[15] 8b 15 to 20°F

Questions people ask

What growing zone is Tacoma?
The center of Tacoma is in USDA zone 8b[1]. By land area, 27% of the city is in ZIP code areas rated zone 9a[15].
When is the last frost in Tacoma?
The median last spring frost at the Tacoma #1 station is March 8, so in half of years the last frost comes after that date[2]. In 1 of 10 years it comes after March 31[2].
When to plant tomatoes in Tacoma?
CSU Extension groups tomatoes as very tender, typically 2 or more weeks after the average last spring frost[11]. Using the median last frost, the earliest start is March 22[11].
When is the first frost in Tacoma?
The median first fall frost is November 14, so in half of years the first frost comes before that date[3]. In 1 of 10 years it comes before October 30[3].
How long is the growing season in Tacoma?
The growing season is at least 250 days in half of years[4]. It is at least 223 days in 9 of 10 years[4].

Facts and sources

  1. The 2023 USDA Plant Hardiness Zone Map puts the center of Tacoma, Washington in zone 8b. Zone 8b means an average annual extreme minimum temperature of 15°F to 20°F over 1991 to 2020. The map's modeled value at the city center is 18.7°F. USDA zone map 2023 (PRISM, OSU)
  2. Last spring frost (32°F) at this station: in 9 of 10 years the last frost comes after February 15, in half of years after March 8, and in 1 of 10 years after March 31 (NOAA 1991 to 2020 normals). The median last frost date is March 8. NOAA Climate Normals 1991-2020
  3. First fall frost (32°F) at this station: in 1 of 10 years the first frost comes before October 30, in half of years before November 14, and in 9 of 10 years before December 2 (NOAA 1991 to 2020 normals). The median first frost date is November 14. NOAA Climate Normals 1991-2020
  4. Growing season (days between the last spring and first fall 32°F frost) at this station: at least 223 days in 9 of 10 years, at least 250 days in half of years, and at least 283 days in 1 of 10 years. NOAA Climate Normals 1991-2020
  5. Frost dates on this page come from NOAA climate normals for the Tacoma #1 weather station (USC00458278), 2.3 miles from the center of Tacoma at 25 feet, using 26 years of records from 1991 to 2020. NOAA Climate Normals 1991-2020
  6. Colorado State University Extension's vegetable planting guide (written for Colorado) groups broccoli, cabbage, kohlrabi, lettuce, onions, peas, radishes, spinach, turnips as hardy vegetables, with this rule: as early as 2-4 weeks before the average last... CSU Extension GardenNotes #720
  7. Hard freeze (28°F) at this station: the median last spring date is February 11 and the median first fall date is December 1. NOAA Climate Normals 1991-2020
  8. At this station the low reached 32°F or colder in 100% of years from 1991 to 2020, and 28°F or colder in 98.5% of years. NOAA Climate Normals 1991-2020
  9. Colorado State University Extension's vegetable planting guide (written for Colorado) groups beets, carrots, cauliflower, parsnips, potatoes, Swiss chard as semi-hardy vegetables, with this rule: as early as 0-2 weeks before the average last spring frost.... CSU Extension GardenNotes #720
  10. Colorado State University Extension's vegetable planting guide (written for Colorado) groups snap beans, sweet corn, cucumbers, summer squash as tender vegetables, with this rule: from seed around the average last spring frost; cucumber and summer squash... CSU Extension GardenNotes #720
  11. Colorado State University Extension's vegetable planting guide (written for Colorado) groups cantaloupe, eggplant, peppers, tomatoes, winter squash, watermelon as very tender vegetables, with this rule: typically 2 or more weeks after the average last... CSU Extension GardenNotes #720
  12. GardenFacts calculation: earliest planting date plus CSU days to harvest (table on this page), from the station's median last frost. NOAA Climate Normals 1991-2020
  13. CSU Extension vegetable table: soil temperature, depth, spacing, days to harvest (table on this page). CSU Extension GardenNotes #720
  14. USDA hardiness zones are based on the average annual extreme minimum winter temperature (the coldest night of each winter, averaged over 1991 to 2020 for the 2023 map), not on summer heat or frost dates. Each zone spans 10°F and each half zone (a or b)... USDA Plant Hardiness Zone Map
  15. Tacoma, Washington overlaps 18 ZIP code areas. By land area, 73% lies in ZIP code areas rated zone 8b, 27% lies in ZIP code areas rated zone 9a. USDA zone map 2023 (PRISM, OSU)

Frost dates are probabilities from 1991 to 2020 weather records at one NOAA station, not a forecast. Any year can be earlier or later. The hardiness zone describes the average coldest winter night, not frost dates or summer heat. Spots inside the city can differ (ZIP table). Planting rules come from Colorado State University Extension's guide, written for Colorado. A local extension office may give dates tuned to the area. Planting and harvest dates marked GardenFacts calculation are simple arithmetic from the facts above, not advice from the source.

Hardiness zone data: USDA Plant Hardiness Zone Map (2023), USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu, accessed October 30, 2026. This is not the official USDA map. Frost data: NOAA NCEI U.S. Climate Normals 1991-2020. Planting rules: Colorado State University Extension.