When to Plant Tomatoes Outdoors in Seattle

Introduction

Tomatoes are a summer favorite, and planting them at the right time is crucial for a successful crop. In Seattle, the weather patterns can be unpredictable, and planting too early or too late can result in a failed harvest. In this article, we'll discuss when to plant tomatoes outdoors in Seattle to ensure you get the best possible yield.

Know Your Average Last Frost Date

Knowing your average last frost date is the first step in planting tomatoes outdoors in Seattle. For most of Seattle, the average last frost date falls between April 10th and April 20th. However, this can vary depending on the location and elevation of your garden. You can easily find your area's average last frost date by using the USDA Plant Hardiness Zone Map.

Preparing the Soil

The soil in Seattle is usually acidic and rich in organic matter. Before planting your tomatoes, it's important to prepare the soil by adding compost, aged manure, or fertilizer. This will improve soil quality and provide the necessary nutrients for your tomato plants to grow strong and healthy. Work the soil to a depth of 8-10 inches, and add the amendments to the soil to a depth of 4-6 inches.

Starting Seeds Indoors

Starting tomato seeds indoors can give your plants a head start and improve their chances of survival. Around 6-8 weeks before your average last frost date, start your tomato seeds indoors. Use a seed starter mix and make sure to keep the soil moist and warm. Place them in a location that receives plenty of sunlight, or use grow lights to provide artificial light.

Planting Tomatoes Outdoors

Around three weeks after your average last frost date, it's time to transplant your tomato seedlings outdoors. Make sure the soil temperature is at least 60°F, and choose a sunny location that gets at least six hours of sunlight. When planting your seedlings, dig a hole twice as large as the root ball, and add a handful of bone meal to the bottom of the hole for added nutrients. Gently remove the seedling from the container, loosen the roots, and place it in the hole. Fill in with soil, and water well.

Caring for Your Tomatoes

Tomatoes require regular attention and care to ensure they receive the necessary nutrients and water. Water your plants regularly, 1-2 inches per week, and avoid getting water directly on the leaves to prevent disease. Stake or trellis your plants to keep them off the ground, and fertilize them with a balanced fertilizer every three weeks. As your tomatoes ripen, harvest them regularly to encourage new growth.

Conclusion

Planting tomatoes outdoors in Seattle requires careful consideration and attention to detail, but the rewards of a successful harvest are well worth the effort. By knowing your average last frost date, preparing the soil, starting seeds indoors, and caring for your plants, you can enjoy a bountiful crop of delicious, homegrown tomatoes.