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In the garden now (2 November 2026)
Seattle planting calendar
Bars show when each crop can go in and when a planting from that window is ready. The blue band is the frost season, from the average first autumn frost to the average last spring frost. Hover or tap a crop for details.
Sow indoorsSow or plant outdoorsHarvestFrost seasonToday
Swipe sideways to see the whole year →
Dates by crop
| Crop | Sow indoors | Sow / plant outdoors | Harvest |
|---|---|---|---|
| Tomato | Apr 11 – May 16 | Jun 6 – Jul 10 plant out | Aug 24 – Oct 12 |
| Pepper | Apr 20 – May 9 | Jun 29 – Jul 4 plant out | Sep 20 – Oct 12 |
| Eggplant (aubergine) | No outdoor window passes all the checks here; grow it under cover or try a specialist variety. | ||
| Cucumber | May 21 – Jun 17 | Jun 18 – Jul 26 sow | Aug 17 – Oct 12 |
| Zucchini (courgette) | May 9 – Jun 5 | Jun 6 – Jul 30 sow | Aug 4 – Oct 12 |
| Pumpkin and winter squash | No outdoor window passes all the checks here; grow it under cover or try a specialist variety. | ||
| Watermelon | Summers are too cool for a reliable outdoor crop. Grow it in a greenhouse or polytunnel. | ||
| Sweet corn | – | May 16 – Jul 2 sow | Aug 24 – Oct 12 |
| Green beans | – | Jun 6 – Jul 26 sow | Aug 9 – Oct 12 |
| Peas | – | Feb 7 – Aug 28 sow | Jun 8 – Nov 24 |
| Lettuce | Jan 9 – Feb 6 | Feb 13 – Sep 10 sow | May 25 – Nov 27 |
| Spinach | – | Feb 9 – Sep 17 sow | May 19 – Dec 17 |
| Kale | Dec 26 – Jan 30 | Feb 6 – Sep 5 sow | Jun 3 – Jan 1 |
| Cabbage | Jan 21 – Feb 25 | Mar 11 – Aug 22 plant out | Jun 24 – Dec 8 |
| Broccoli | Jan 21 – Feb 25 | Mar 11 – Aug 29 plant out | Jun 15 – Dec 1 |
| Carrots | – | Mar 11 – Aug 28 sow | Jun 20 – Jan 1 |
| Beets (beetroot) | – | Mar 11 – Sep 3 sow | Jun 11 – Dec 8 |
| Radishes | – | Mar 4 – Oct 2 sow | May 4 – Dec 1 |
| Onions | Dec 5 – Jan 9 | Feb 13 – Aug 1 plant out | Jul 9 – Nov 17 |
| Garlic | – | Sep 29 – Nov 2 sow | Jul 6 – Jul 26 |
| Potatoes | – | Mar 29 – Aug 4 sow | Jul 15 – Nov 17 |
| Swiss chard | – | Mar 29 – Sep 7 sow | Jun 12 – Dec 8 |
| Basil | May 18 – Jun 15 | Jun 29 – Aug 19 plant out | Jul 31 – Oct 12 |
| Cilantro (coriander) | – | Mar 11 – Sep 20 sow | May 21 – Dec 1 |
| Parsley | Feb 1 – Mar 8 | Mar 29 – Aug 23 sow | Jun 29 – Dec 17 |
Dates are for a typical year and the middle of the window is the safest. Sow a little at a time across a window rather than all at once. Cold snaps, heat waves, frost pockets and city warmth all shift the real dates; watch the forecast.
Frost dates in Seattle
- Average last spring frost
- March 13
- Late frost (1 year in 10)
- April 1
- Average first autumn frost
- November 17
- Early frost (1 year in 10)
- November 1
- Frost-free growing season
- 248 days
“Average” is the date with an even chance of a later (spring) or earlier (autumn) frost: a night at or below 0 °C (32 °F) at screen height. Tender crops go out a week or two after the spring date, which brings the risk down to about one year in ten.
Source: NOAA 1991–2020 normals, Seattle Boeing Fld (7 km from the city centre).
Climate at a glance
- Hardiness zone
- 9a from station records
- Average coldest winter night
- -6°C21°F
- Warmest month
- August, highs 24°C76°F
- Coldest month
- December, lows 2°C36°F
- Crops with an outdoor window
- 22 of 25
The zone follows the USDA scheme: bands of the average lowest temperature of the year, 10 °F wide, split into a and b halves. Worked out from the coldest night of each year 1991–2020 at the NOAA station. It tells you which perennials survive winter, not when to sow.
Temperature and rain by month
Average highAverage lowRainFreezing point
| Month | High | Low | Mean | Rain |
|---|---|---|---|---|
| January | 8°C47°F | 3°C37°F | 5°C42°F | 136 mm5.4 in |
| February | 10°C49°F | 3°C37°F | 6°C43°F | 90 mm3.5 in |
| March | 12°C53°F | 4°C39°F | 8°C46°F | 111 mm4.4 in |
| April | 14°C58°F | 6°C42°F | 10°C50°F | 75 mm3.0 in |
| May | 18°C65°F | 9°C48°F | 13°C56°F | 45 mm1.8 in |
| June | 21°C70°F | 11°C52°F | 16°C61°F | 40 mm1.6 in |
| July | 24°C75°F | 13°C56°F | 19°C65°F | 19 mm0.8 in |
| August | 24°C76°F | 13°C56°F | 19°C66°F | 28 mm1.1 in |
| September | 21°C70°F | 11°C52°F | 16°C61°F | 40 mm1.6 in |
| October | 15°C60°F | 7°C45°F | 11°C53°F | 95 mm3.7 in |
| November | 10°C51°F | 4°C40°F | 8°C46°F | 146 mm5.8 in |
| December | 8°C46°F | 2°C36°F | 5°C41°F | 149 mm5.9 in |
Monthly averages 1991–2020 from TerraClimate (about 4 km grid).