When To Plant Vegetables In Washington

Knowing when to plant vegetables in Washington is the single biggest factor for a great harvest. Our unique climate, with its wet springs, dry summers, and varied regions, makes timing everything. Get it right, and your garden will thrive. Get it wrong, and you might face stunted growth or no veggies at all. This guide will walk you through the simple steps to perfect your planting schedule.

First, you need to know your Washington garden zone. The state has everything from rainy coastal areas to dry eastern plains and high mountain zones. The USDA plant hardiness map is your best starting point. Most of western Washington is in zones 8a to 9a. Eastern Washington spans zones 5a to 7a. Your last spring frost date depends on this. In Seattle (zone 8b), the last frost is around mid-March. In Spokane (zone 6a), it’s often near mid-May. Check your local frost dates online for the most accurate info.

This heading is your master principle. We break it down by season and vegetable type. The key is understanding cool-season vs. warm-season crops. Cool-season veggies can handle frost and even taste better in cooler weather. Warm-season crops need warm soil and air; they’ll fail if planted too early.

Early Spring Planting (February – April)

As soon as the soil is workable—not too wet or muddy—you can start. This is for cool-season crops. You can sow seeds directly or use transplants for a head start.

Direct Seed Outdoors: Peas, spinach, kale, radishes, and arugula. You can plant these as early as late February in western WA if the soil isn’t waterlogged.
Start Indoors (for transplanting later): Broccoli, cabbage, cauliflower, and lettuce. Start these inside 6-8 weeks before your last frost date.
Transplant Outdoors: In March/April, you can move hardened-off broccoli, cabbage, and kale plants into the garden. Protect them if a hard frost is expected.

Late Spring to Early Summer (May – June)

This is the main planting window after the danger of frost has passed. The soil is finally warming up.

Direct Seed Warm-Season Crops: Beans, corn, cucumber, and squash. Wait until soil temps are consistently above 60°F. In western WA, this is often late May. In eastern WA, wait until early June in some spots.
Transplant Warm-Season Tender Crops: This is for tomatoes, peppers, eggplants, and basil. Do not rush these! Planting tomatoes in cold, wet soil will shock them. Wait until nights are reliably above 50°F. Using season extenders like wall-o-waters can help in cooler areas.
Succession Plant Cool-Season Crops: Sow more lettuce, carrots, and beets for a continous harvest into fall.

Midsummer Planting (July – August)

This is your chance to plan for a fall and winter harvest. Many gardeners miss this second season.

Direct Seed for Fall: In July, plant carrots, beets, bush beans, and scallions. They’ll mature in the cooler autumn weather.
Plant Overwintering Crops: In late July to August, sow kale, Brussels sprouts, and certain broccoli varieties. These will grow slowly through fall and winter for an early spring harvest.

Regional Adjustments Across Washington

Our state isn’t one-size-fits-all. Here’s how to adjust.

Western Washington (Coastal & Puget Sound)

You have mild, wet winters and cool summers. Your main challenges are cool soil and slugs.

Start warm-season crops indoors. Use black plastic or cloches to warm garden soil in spring.
Take full advantage of the long, mild fall. Your fall planting window is longer than anywhere else.
Watch for late spring rains causing rot; ensure good drainage.

Eastern Washington

You have colder winters, hotter summers, and less rainfall. Frost dates are critical.

Your growing season is shorter but more intense. Choose vegetable varieties with shorter days to maturity.
Use mulch heavily to conserve soil moisture and moderate soil temperature.
You can often plant quick-cool season crops (like lettuce) again in late summer for a fall harvest, as the heat breaks earlier.

Step-by-Step Planting Calendar

Here is a simplified month-by-month guide. Adjust based on your exact location and yearly weather.

February – March: Prep garden beds if soil is workable. Direct sow peas, spinach, radish. Start broccoli, cabbage indoors.
April: Transplant early cool-season crops. Direct sow carrots, chard, beet. Start tomato and pepper seeds indoors.
May: Last frost is likely past. Transplant tomatoes, peppers, eggplants after hardening off. Direct sow beans, corn, squash.
June: Direct sow successions of lettuce, beans. Ensure consistent watering as things heat up.
July: Plant fall-harvest carrots, beets, and bush beans. Sow overwintering kale and sprouts.
August: Final planting of fall greens like spinach and lettuce. Garlic planting begins in late October.

Pro Tips for Success

Invest in a Soil Thermometer: This takes the guesswork out. Plant warm-season crops only when soil is warm enough.
Harden Off Transplants: Always acclimate indoor-started plants to outdoor conditions over 7-10 days. This prevents sun scald and shock.
Use Season Extenders: Cold frames, row covers, and cloches protect early and late plantings from frost, giving you extra weeks.
Keep a Garden Journal: Note planting dates, varieties, and what worked. This is your best tool for improving each year. Weather can vary a lot from one year to the next.

Common Mistakes to Avoid

Planting Too Early (Especially Warm-Season Crops): Impatience is the biggest cause of failure. Warm soil is more important than a warm air day.
Ignoring Soil Preparation: Washington soils often need organic matter. Add compost in the fall or early spring to improve drainage and fertility.
Overcrowding Plants: Follow spacing on seed packets. Good air flow prevents fungal diseases common in our damp springs.
Forgetting to Rotate Crops: Don’t plant the same family (like tomatoes/peppers/eggplant) in the same spot year after year. It helps prevent pest and disease buildup.

FAQ: When to Plant Vegetables in Washington

What month do you start a vegetable garden in Washington?

You can start as early as February with cool-season seeds like peas and spinach, especially in western WA. The main garden planting happens from April through June.

When should I plant tomatoes in Washington state?

Wait until after your last frost date. For most, this is mid-to-late May. Ensure nighttime temperatures are consistently above 50°F. Using protection can allow for slightly earlier planting.

Can you grow vegetables year-round in Washington?

Yes, with planning. Overwintering crops like kale, garlic, and some brassicas can survive. Using cold frames or hoop houses extends the season significantly for harvests through winter.

What are the best vegetables to grow for beginners in WA?

Start with easy, cool-season crops: lettuce, radishes, peas, and kale. They are forgiving and can be planted early. Bush beans and zucchini are also great for summer.

Getting your timing right makes gardening in Washington much more rewarding. By following these regional and seasonal guidelines, you’ll work with our climate, not against it. Start with a few crops you love, keep notes, and enjoy the process of growing your own food. There’s nothing quite like the taste of a vegetable picked from your own garden at its perfect moment.