When to Plant Spinach in Washington (2026 Guide)
Growing spinach in Washington can be a rewarding experience, especially for those who appreciate cool-season crops. Spinach is a nutritious vegetable that thrives in cooler temperatures, making it perfect for early spring and fall plantings. In areas like Arlington and Bellevue, the last spring frost typically occurs around April 9, ensuring a good window for planting before the summer heat arrives.
As the weather begins to warm up, it's essential to time your spinach planting effectively to avoid bolting. In many regions across Washington, including Auburn and Battle Ground, the median last spring frost occurs later, around April 20. However, by carefully managing your planting schedule, you can enjoy a continuous harvest throughout the season.
Whether you’re in Seattle with its mild maritime climate or in Spokane where conditions can be slightly harsher, understanding the local frost dates is key. For example, those in colder regions like Olympia should note that the last spring frost is around May 6. With the right timing, you can successfully grow spinach and enjoy fresh greens from your garden.
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 March 15 – April 15, after last frost | Direct sow March 1 – April 15, before last frost | Harvest from April 25 – June 10, throughout early summer |
| Zone 6a | Start February 20 – March 5, ~6–8 weeks before April 20 | Transplant outdoors March 25 – April 25, after last frost | Direct sow March 10 – April 25, before last frost | Harvest from May 5 – June 20, throughout early summer |
| Zone 5b | Start March 10 – March 20, ~6–8 weeks before May 6 | Transplant outdoors April 15 – May 1, after last frost | Direct sow March 20 – April 30, before last frost | Harvest from May 15 – June 30, throughout early summer |
Spinach Planting Windows in Washington
- Indoor start: For most areas in Washington, the ideal window for starting spinach indoors is from February 15 to March 5.
- Transplant outdoors: Transplanting outdoors should be done between March 15 and April 25 in Washington, depending on your specific zone.
- Harvest: You can expect to begin harvesting spinach from April 25 to June 30, depending on your planting dates and local conditions.
Common Mistakes Growing Spinach in Washington
- One common mistake in Washington is planting too late. Due to varying last frost dates and cooler spring temperatures, many gardeners miss the optimal window, leading to disappointing yields.
- Overlooking the importance of soil temperature is another frequent mistake. Spinach thrives when sown into soil temperatures of around 40°F, and if planted too early in cold, wet soil, seeds may rot.
- Many gardeners in Washington fail to account for the humidity. High humidity levels can lead to disease problems, which might affect your spinach if proper spacing and airflow are not managed.
- Another issue is planting spinach too close to heat-absorbing materials, such as concrete or large stones. This can lead to overheating, causing early bolting and lower yields.
- Lastly, some local gardeners mistakenly believe that spinach does not benefit from succession planting. To maximize your harvest in Washington, sow seeds every 2-3 weeks to stagger your yields and extend the growing season.
Frequently Asked Questions
What if I'm in a cold pocket of Washington?
If you're situated in a colder area, be sure to follow the last frost dates closely. Consider starting your spinach indoors or using row covers to protect young plants, ensuring a successful early harvest.
Can I still plant spinach in May?
It's not ideal to plant spinach in May, especially since it could lead to bolting due to rising temperatures. If you do plant later, choose bolt-resistant varieties to extend your harvest.
How often should I water my spinach?
Water spinach consistently, keeping the soil moist but not soggy. Aim for about 1 inch of water per week, adjusting based on weather conditions, particularly in the heat of Washington summers.
What's the best way to harvest spinach?
The best technique is to harvest the outer leaves and leave the center intact. This encourages more growth and allows for a longer harvesting period, giving you fresh spinach for weeks.
Are there specific spinach varieties suited for Washington?
Yes, consider growing varieties like 'Bloomsdale Long Standing' or 'Space,' which are known for their bolt resistance and can handle the cooler growing conditions found throughout Washington.
Keep Learning
City guides in Washington
Other crops in Washington
Typical fall sowing window for Spinach in Washington: September 1 – September 22.