When to plant · 31 cities · zones 7a–9a
When to plant basil in Washington
Start Genovese Basil seeds indoors around Mar 17 and transplant around Apr 28 — the Washington statewide median, counted from a last spring frost of Apr 14 across 597 ZIP codes and 156 NOAA stations.
The rule: Basil is damaged below about 50 °F, well before frost: transplant two weeks after the last frost, not on it.
Washington basil, by step
Statewide median last frost Apr 14, first fall frost Oct 25, 2027 season. Each cultivar's own indoor lead time and days to maturity, same engine as the Plan Builder.
| Cultivar | Start indoors | Plant out | First harvest | Days |
|---|---|---|---|---|
| Genovese BasilGenovese | Mar 17 | Apr 28 | Jun 27 | 60 from transplant |
Tight means first harvest lands within two weeks of the median first fall frost. Statewide dates are the ZIP-weighted median of every NOAA 1991–2020 station Washington's ZIP codes resolve to; 5 of 602 ZIPs have no datable freeze and are left out.
Basil in Washington, city by city
Genovese Basil, scheduled from each city's nearest NOAA station — the same dates as its frost page.
| City | Last frost | Start indoors | Plant out | First harvest |
|---|---|---|---|---|
| Seattlezone 9a | Mar 13 | Feb 13 | Mar 27 | May 26 |
| Spokanezone 7a | Apr 26 | Mar 29 | May 10 | Jul 9 |
| Tacomazone 8b | Mar 8 | Feb 8 | Mar 22 | May 21 |
| Vancouverzone 8b | Mar 29 | Mar 1 | Apr 12 | Jun 11 |
| Bellevuezone 9a | Mar 8 | Feb 8 | Mar 22 | May 21 |
| Kentzone 8b | Mar 20 | Feb 20 | Apr 3 | Jun 2 |
| Everettzone 8b | Mar 24 | Feb 24 | Apr 7 | Jun 6 |
| Spokane Valleyzone 7a | Apr 26 | Mar 29 | May 10 | Jul 9 |
| Rentonzone 9a | Mar 13 | Feb 13 | Mar 27 | May 26 |
| Federal Wayzone 8b | Mar 8 | Feb 8 | Mar 22 | May 21 |
| Yakimazone 7a | Apr 8 | Mar 11 | Apr 22 | Jun 21 |
| Bellinghamzone 8b | Apr 1 | Mar 4 | Apr 15 | Jun 14 |
| Kirklandzone 9a | Mar 8 | Feb 8 | Mar 22 | May 21 |
| Kennewickzone 7b | Mar 28 | Feb 28 | Apr 11 | Jun 10 |
| Auburnzone 8b | Mar 20 | Feb 20 | Apr 3 | Jun 2 |
| Redmondzone 8b | Mar 8 | Feb 8 | Mar 22 | May 21 |
| Pascozone 7b | Mar 28 | Feb 28 | Apr 11 | Jun 10 |
| Marysvillezone 8b | Mar 24 | Feb 24 | Apr 7 | Jun 6 |
| Sammamishzone 8b | Mar 30 | Mar 2 | Apr 13 | Jun 12 |
| Shorelinezone 9a | Mar 8 | Feb 8 | Mar 22 | May 21 |
| Richlandzone 7b | Apr 6 | Mar 9 | Apr 20 | Jun 19 |
| Lakewoodzone 8b | Mar 8 | Feb 8 | Mar 22 | May 21 |
| Laceyzone 8b | Apr 29 | Apr 1 | May 13 | Jul 12 |
| Olympiazone 8b | Apr 29 | Apr 1 | May 13 | Jul 12 |
| Burienzone 9a | Mar 2 | Feb 2 | Mar 16 | May 15 |
| Bothellzone 8b | Mar 8 | Feb 8 | Mar 22 | May 21 |
| Bremertonzone 8b | Mar 29 | Mar 1 | Apr 12 | Jun 11 |
| Edmondszone 9a | Mar 9 | Feb 9 | Mar 23 | May 22 |
| Puyallupzone 8b | Apr 11 | Mar 14 | Apr 25 | Jun 24 |
| Lynnwoodzone 9a | Mar 9 | Feb 9 | Mar 23 | May 22 |
| Lake Stevenszone 8b | Mar 24 | Feb 24 | Apr 7 | Jun 6 |
What these basil become
What Washington basil need
Genovese Sweet Basil Seed
The large-leaf, low-anise Italian basil that pesto is defined by. Thai and lemon basils are good plants and wrong ingredients.
Organic Seed Starter Potting MixMust have
Seed-starting mix is not potting soil with a nicer label — it is finer, lighter, and low in nutrients on purpose, because a seedling's first roots want air and moisture, not fertiliser.
T8 Full-Spectrum Grow Lights, 1 ft 4-packMust have
A south window in March delivers a fraction of the light a pepper seedling needs, and the plant tells you by stretching. Two inches of LED above the canopy for 16 hours a day fixes it permanently.
5-Gallon Fabric Grow Bags, 5-Pack
Fabric pots air-prune roots and drain faster than a plastic pot can, which is the entire reason container tomatoes fail. Five gallons is the honest minimum for a pepper; a tomato wants ten.
Ocean Forest Potting SoilMust have
Pre-charged with enough nutrition to carry a transplant for its first month without feeding, which is exactly the window when most container plants stall.
6" Micro-Tip Pruning SnipsMust have
Ninety percent of sauce-garden cutting is snipping a pepper stem or a basil node, and a fine-tipped snip does it better than any pruner. Pulling peppers by hand tears the branch.
Mesh Strainers, Stainless, 3-Count
The last pass before bottling. A fine mesh catches the skin fragments and seed shards that make a hot sauce gritty and clog a woozy bottle's dripper insert.
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Basil in Washington: questions
When should I plant basil in Washington?
Transplant around Apr 28 at the statewide median; across the state that date runs from Mar 22 in the warmest tenth of Washington's ZIP codes to May 27 in the coldest. To cut the freeze risk to one year in ten, count from May 5 instead of the median last frost. Use the city table for your own town.
When do I start basil seeds indoors in Washington?
Around Mar 17 for Genovese Basil: 4 weeks before the statewide median last frost, on soil held at 70–80 °F.
When is the last frost in Washington?
The ZIP-weighted median of NOAA 1991–2020 station medians is Apr 14. In the warmest tenth of Washington's ZIP codes the median last frost falls on or before Mar 8; in the coldest tenth, on or after May 13.
When will Washington basil be ready to harvest?
Genovese Basil planted on the statewide date is ready around Jun 27: 60 days from transplant.
More for Washington
- When to plant tomatoes
- When to plant peppers
- When to plant tomatillos
- When to plant onions
- When to plant cilantro
- When to plant carrots
- When to plant mustard greens
Basil in every state → · Washington frost dates → · How frost-date math works →