When to Plant Arugula in Washington (2026 Guide)
Growing arugula in Washington can be incredibly rewarding due to the state's varied climates, particularly in the vibrant spring and early fall months. In the warmer regions, like Seattle, gardeners can expect to see arugula thrive when planted 4-6 weeks before the last spring frost on April 9, allowing for an early harvest that showcases its distinctive peppery flavor. Late summer plantings are also popular for a fall harvest, particularly before the first fall frost on October 26.
Because arugula is a cool-season crop, timing is essential to avoid the rapid bolting that occurs in warmer temperatures. With a growing season lasting approximately 200 days in places like Seattle and Bellevue, understanding when to plant can make a significant difference. With careful planning, you can enjoy fresh arugula from your garden consistently throughout the growing season by staggering sowings every few weeks.
Many gardeners in Washington make the most of limited space by intercropping arugula with slower-growing plants like carrots and beets. This strategy takes advantage of arugula's quick growth cycle of about 40 days from seed to harvest. The overlap allows gardeners to maximize their yield while enjoying the different textures and flavors that arugula adds to salads and meals.
Planting Schedule by USDA Zone in Washington
| Zone | Indoor start | Transplant out | Direct sow | Harvest |
|---|---|---|---|---|
| Zone 6b | Start February 15 – March 1, ~6–8 weeks before April 9 | Transplant outdoors April 1 – April 10 | Direct sow outdoors April 1 – April 10 | Harvest from May 10 – June 20 |
| Zone 6a | Start March 1 – March 15, ~6–8 weeks before April 20 | Transplant outdoors April 10 – April 20 | Direct sow outdoors April 10 – April 20 | Harvest from May 20 – July 1 |
| Zone 5b | Start March 15 – April 1, ~6–8 weeks before May 6 | Transplant outdoors April 25 – May 6 | Direct sow outdoors April 25 – May 6 | Harvest from June 10 – July 20 |
Arugula Planting Windows in Washington
- Indoor start: For Washington gardeners, the indoor sowing window for arugula typically runs from February 15 to March 15.
- Transplant outdoors: Plan to transplant outdoors between April 1 and April 20, after the last frost date.
- Harvest: You can expect your first arugula harvest between May 10 and July 20, depending on when you sowed the seeds.
Common Mistakes Growing Arugula in Washington
- One typical mistake is planting arugula too late in spring when temperatures rise quickly. Washington’s late spring heatwaves can cause plants to bolt before you can reap any benefits.
- Many novice gardeners in Washington overwater their arugula, leading to issues like root rot and disease. Ensure your soil drains well and adjust your watering schedule according to rainfall.
- Another common error is failing to succession sow arugula. By spacing sowings 2-3 weeks apart, you can maintain a fresh supply, instead of having all your crops ready at once.
- Assuming that all varieties of arugula grow well in extreme heat is another mistake. Washington's weather can vary; choose heat-resistant varieties if planting during warmer months to avoid bolting.
- Not rotating crops can lead to disease buildup in the soil. Growing arugula consecutively in the same spot year after year in Washington can increase vulnerability to pests and diseases.
Frequently Asked Questions
What if I'm in a cold pocket of Washington?
In colder areas, consider starting your arugula seeds indoors earlier, around February 15. This gives you more control over your planting and helps ensure successful germination when you finally transplant outdoors.
Can I still plant arugula in May?
Planting in May is possible in some areas of Washington, but be cautious. As temperatures rise, your arugula is likely to bolt quickly, which will impact flavor. Consider planting heat-resistant varieties.
How often should I water my arugula?
It’s essential to keep the soil consistently moist but not soggy. Water deeply about once a week in Washington. Pay attention to rainfall, especially during our rainy spring season, to avoid overwatering.
How can I keep pests away from my arugula?
Using floating row covers at the time of sowing can prevent pests like flea beetles from damaging your arugula. Just remember to remove them once plants begin to bolt to ensure proper air circulation.
Why is my arugula getting bitter?
Bitterness in arugula often signals that your plants are about to bolt. Washington's fluctuating temperatures can trigger this, especially when they experience sudden heat. Regular harvesting of young leaves helps maintain a milder taste.
Keep Learning
City guides in Washington
Other crops in Washington
Typical fall sowing window for Arugula in Washington: September 1 – September 22.