Frost dates · USDA zone 9a
Frost dates for Gresham, OR
Gresham, OR sees its last 32 °F night of spring around March 16 and its first of fall around November 20 — a 250-day freeze-free season in a typical year.
Pick a sauce; the Plan Builder runs this station's dates and hands back the calendar, plant count and gear list.
Freeze odds, by date
| Odds | Last spring freeze after | First fall freeze before |
|---|---|---|
| 9 years in 10 | Feb 18 | Dec 17 |
| Median — 1 year in 2 | Mar 16 | Nov 20 |
| 1 year in 10 | Apr 12 | Oct 30 |
The top row is the risky edge: in 9 years of 10 a spring freeze still comes after it, so tender transplants set out then need cover. The bottom row is the cautious date — only 1 year in 10 freezes after it — and the one to plan uncovered tender transplants against. Freeze-free season: 250 days median, at least 216 in 9 years of 10, at least 288 days in 1 year of 10. NOAA ranks season length year by year, so it is not the gap between two rows above. A hard freeze (28 °F) has a median last date of Feb 14 and first of Dec 15.
Gresham planting calendar, 2027
Every row runs from the median last frost (Mar 16) and median first frost (Nov 20) above, using each cultivar's days to maturity. Same engine as the Plan Builder.
| Crop | Start indoors | Transplant / plant | First harvest | Days |
|---|---|---|---|---|
| Hardneck GarlicSiberian (porcelain hardneck) | — | Oct 15prior fall | Jun 12 | 240 from sow |
| Spanish OnionYellow Sweet Spanish (long-day) | Dec 22 | Feb 16 | Jun 6 | 110 from transplant |
| Mustard greensGarnet Giant (Brassica juncea) | Direct sow | Mar 16 | Apr 15 | 30 from sow |
| CilantroSlow Bolt (Coriandrum sativum) | Mar 2 | Mar 2 | Apr 16 | 45 from sow |
| Genovese BasilGenovese | Feb 16 | Mar 30 | May 29 | 60 from transplant |
| CayenneLong Slim Cayenne (Capsicum annuum) | Jan 19 | Mar 23 | Jun 6 | 75 from transplant |
| HabaneroOrange Habanero (Capsicum chinense) | Jan 5 | Mar 30 | Jul 3 | 95 from transplant |
| JalapeñoEarly Jalapeño (Capsicum annuum) | Jan 19 | Mar 23 | Jun 6 | 75 from transplant |
| Marconi Red PepperMarconi Red (Capsicum annuum) | Jan 19 | Mar 23 | Jun 11 | 80 from transplant |
| SerranoSerrano Tampiqueño (Capsicum annuum) | Jan 19 | Mar 23 | Jun 11 | 80 from transplant |
| Nantes CarrotScarlet Nantes | Mar 2 | Mar 2 | May 11 | 70 from sow |
| TomatilloToma Verde | Feb 2 | Mar 23 | Jun 1 | 70 from transplant |
| Roma TomatoRoma VF (determinate paste) | Feb 2 | Mar 23 | Jun 6 | 75 from transplant |
| San Marzano TomatoSan Marzano (indeterminate paste) | Feb 2 | Mar 23 | Jun 11 | 80 from transplant |
Tight means first harvest lands within two weeks of the median first fall frost: start that crop indoors on time or cover it in fall.
What sauce can Gresham grow?
Each sauce, scheduled for a Gresham container garden: when the first seeds go in and when enough fruit has ripened for one batch.
Gresham frost questions
When is the last frost in Gresham, OR?
The median last 32 °F freeze at PORTLAND TROUTDALE AP, OR is March 16: half of years see a later one. One year in ten, a freeze still comes after April 12; nine years in ten, it comes after February 18. Source: NOAA NCEI 1991–2020 U.S. Climate Normals.
When is the first frost in Gresham, OR?
The median first 32 °F freeze of fall is November 20. One year in ten it arrives before October 30; nine years in ten, before December 17.
How long is the growing season in Gresham, OR?
250 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 216 days; one year in ten, at least 288 days.
What growing zone is Gresham, OR?
USDA hardiness zone 9a, per the 2023 USDA Plant Hardiness Zone Map for ZIP 97030. A zone describes the coldest winter night, not when frost ends, so it is the wrong number for a planting calendar — the frost dates on this page are the right one.
When should I plant tomatoes in Gresham, OR?
Start Roma VF (determinate paste) seeds indoors around Feb 2 and transplant around Mar 23, 1 week after the median last frost. To cut the freeze risk to one year in ten, wait for Apr 12. First ripe fruit lands around Jun 6.
When should I plant peppers in Gresham, OR?
Sow jalapeño indoors on a heat mat around Jan 19; transplant no earlier than Mar 23, and wait past it until nights hold above 50 °F — that can run weeks later. First green pods around Jun 6.
Nearby in Oregon
- Portlandlast frost Feb 25
- Tigardlast frost Apr 1
- Beavertonlast frost Feb 11
- Hillsborolast frost Apr 16
- Salemlast frost Apr 3
- Albanylast frost Apr 17
All Oregon frost dates → · How frost-date math drives a sowing calendar →