Washington Garden Guide: Planting Dates, Frost Dates & Growing Seasons
Washington’s west-east mountain divide creates dramatically different growing conditions.
In a typical year, the growing season in Washington runs roughly from April 17 through October 25, giving many parts of the state about 191 frost-free days. Use this page as a statewide baseline, then compare local city pages for more precise planting timing.
Growing Season Snapshot
Washington contains a sharp split between marine and interior gardening realities. West-side gardens often have a softer but slower season, while east-side locations can warm harder and faster but often do so under drier, more swingy conditions. In practice, the state rewards regional judgment more than broad assumptions.
These season boundaries are climate normals, not a forecast. A 50% frost date means a 32°F frost arrives by that date in about half of years — and later in about half. Treat these dates as planning anchors, not guarantees.
Washington Planting Calendar
A practical guide to when planting usually works in Washington. These windows are based on climate normals (not a forecast) and line up with the 50% last spring frost and typical early-season heat.
| Crop | Planting Window | Method |
|---|---|---|
| Cool-season / early window Cold-tolerant crops that usually handle cooler spring conditions better. | ||
| Peas | March 20 – April 3 | direct sow |
| Spinach | March 20 – April 3 | direct sow |
| Lettuce | March 27 – April 10 | direct sow / transplant |
| Strawberries | March 27 – April 10 | plant crowns / transplants |
| Carrots | March 27 – April 10 | direct sow |
| Beets | March 27 – April 10 | direct sow |
| Radishes | March 20 – April 3 | direct sow |
| Potatoes | April 3 – April 17 | plant seed potatoes |
| Onions | March 27 – April 10 | sets / transplants |
| Garlic | March 29 – April 8 | plant cloves |
| Broccoli | April 3 – April 17 | transplant |
| Cauliflower | April 3 – April 17 | transplant |
| Cabbage | April 3 – April 17 | transplant |
| Kale | March 24 – April 13 | direct sow / transplant |
| Swiss chard | March 28 – April 17 | direct sow / transplant |
| Main warm-season window Crops that usually do best once frost risk fades and the season starts opening up more fully. | ||
| Beans | April 17 – May 1 | direct sow |
| Sweet corn | April 22 – May 2 | direct sow |
| Cucumbers | April 26 – May 6 | direct sow / transplant |
| Zucchini | April 26 – May 6 | direct sow / transplant |
| Squash | April 26 – May 6 | direct sow / transplant |
| Melons | April 26 – May 6 | direct sow / transplant |
| Watermelons | April 26 – May 6 | direct sow / transplant |
| Basil | April 26 – May 6 | direct sow / transplant |
| Tomatoes | April 26 – May 6 | transplant |
| Peppers | May 3 – May 13 | transplant |
How to use this: aim for the earlier part of each window for the most reliable results. Later planting can still work, but it usually depends more on variety maturity, warmer microclimates, and simple protection like row cover or low tunnels.
Common Timing Mistakes
These patterns show up again and again in Washington — especially in typical years.
- Planting everything at once instead of staggering crops across the season.
- Assuming conditions are uniform across the region — frost timing often varies widely by elevation, exposure, and shelter.
- Relying on calendar dates instead of crop maturity and typical frost timing.
Frost Dates and Growing Conditions Across Washington Cities
Growing conditions often vary more within Washington than most gardeners expect. Differences in elevation, exposure, cold-air drainage, and nearby pavement or buildings can shift frost timing and change how much usable season you really have.
| City | Last spring frost | First fall frost | Frost-free days | Remaining GDD (May 15 → Aug 1, base 50) |
|---|---|---|---|---|
| Spokane | Apr 26 | Oct 12 | 169 | 2222 → 1013 |
| Yakima | May 05 | Oct 04 | 152 | 2730 → 1277 |
| Wenatchee | Apr 04 | Oct 28 | 207 | 2877 → 1331 |
| Walla Walla | Mar 27 | Oct 31 | 218 | 2353 → 1056 |
| Everett | Mar 24 | Nov 02 | 223 | 1770 → 848 |
| Olympia | Apr 29 | Oct 14 | 168 | 1569 → 757 |
| Tacoma | Mar 08 | Nov 14 | 251 | 1732 → 852 |
| Seattle | Mar 13 | Nov 17 | 249 | 2124 → 1049 |
| Mount Vernon | Mar 24 | Nov 03 | 224 | 1582 → 752 |
| Vancouver | Apr 26 | Oct 18 | 175 | 1736 → 850 |
| Port Angeles | Mar 12 | Nov 19 | 252 | 1255 → 619 |
| Bremerton | Mar 29 | Nov 14 | 230 | 1864 → 935 |
| Moses Lake | Apr 27 | Oct 08 | 164 | 2470 → 1133 |
| Bellingham | Apr 01 | Nov 02 | 215 | 1670 → 790 |
- Frost timing varies widely across the region, especially between colder pockets and more sheltered sites.
- Earlier-frost and shorter-season locations usually need faster-maturing crops and tighter planting timing.
- Warmer locations usually retain more remaining heat through the season, giving longer-season crops and later plantings better odds of finishing.
- Urban areas, walls, and sheltered gardens usually stay warmer than open rural or wind-exposed sites.
- Cold air settles in low spots, so slightly elevated beds often avoid the earliest frosts.
- South- and west-facing areas usually warm sooner in spring and can stay productive later into fall.
How the Growing Season Works in Washington
Washington usually has a relatively forgiving season, but results still depend on how quickly gardens warm in spring and how well crop choices match local conditions.
- Stagger planting dates: spreading sowings and transplanting windows often works better than planting everything at once.
- Fall planting is more realistic: many areas still have enough runway for a meaningful second round of faster crops.
- Summer management becomes the limiter: water, fertility, and pest pressure often matter more than season length alone.
Microclimate note: frost timing varies widely across Washington, so sheltered gardens, urban sites, and warmer exposures can behave very differently from colder open areas.
Late-summer note: there is often still meaningful heat left around early August, so second plantings of faster crops can still be worthwhile.
Remaining Season Heat in Washington (Base 50 GDD)
Growing Degree Days (Base 50°F) measure heat accumulation. “Remaining GDD” shows how much usable heat is typically still available from a given date onward in a normal season.
| Planting date | Base | Typical GDD still available |
|---|---|---|
| May 15 | 50 | 1852 |
| June 1 | 50 | 1728 |
| July 1 | 50 | 1407 |
| August 1 | 50 | 852 |
Use these values to judge whether a crop or variety still has enough heat left after planting. This is especially helpful for later sowings, shorter-maturity choices, and deciding whether a second round is realistic.
How Gardeners Adapt
Experienced gardeners in Washington usually adjust their timing and crop choices to match how the season actually behaves, not just the calendar.
- Using row cover or low tunnels to smooth out temperature swings early and late in the season.
- Succession planting fast crops to keep beds productive through summer.
- Watching local conditions closely and adjusting timing year by year.
Washington Garden Planning Chart
A practical “typical year” for planning. Use it as a baseline, then adjust for microclimates and variety maturity.
| Stage | What it usually means |
|---|---|
| Early season | Start cold-tolerant crops, prep beds, and pay more attention to soil warmth and night temperatures than to the calendar alone. |
| Main planting | Around April 17, the main planting push usually begins as frost risk fades. Warm-season crops generally perform best when they get established promptly. |
| Peak growth | This is when water, fertility, spacing, and pest pressure have the biggest effect on final yield. |
| Late-summer decisions | There is often enough late-season heat left for a meaningful second round of quick crops. |
| Finish window | Plan to have frost-sensitive crops mostly wrapped up by October 25. Cooling nights often slow crops before the first real frost arrives. |
Typical season length: 191 frost-free days between the median spring and fall frost dates.