Washington’s August weather supports vegetables that thrive in cooler evenings and moderate daytime temperatures. If you are looking for the best vegetables to plant in august in washington, you have come to the right place. August can be a tricky month for gardening in the Pacific Northwest, but with the right choices, you can enjoy a bountiful fall harvest. This guide will walk you through the top vegetables to plant now, along with practical tips for success.
Many gardeners think August is too late to plant anything. That is not true. In Washington, the soil is warm, and the days are still long. This creates perfect conditions for fast-growing crops. You just need to pick varieties that mature quickly and can handle cooler nights.
Let’s get straight into the best options for your August garden. We will cover leafy greens, root vegetables, and even some brassicas. Each recommendation includes planting depth, spacing, and days to maturity. You will also find advice on watering and soil prep.
Best Vegetables To Plant In August In Washington
This section covers the top performers for late-summer planting. These vegetables are chosen for their ability to germinate in warm soil and mature before the first frost. Washington’s climate zones vary, but these picks work well across most regions, from the Puget Sound to the Columbia Basin.
Leafy Greens For Quick Harvests
Leafy greens are your best bet for August planting. They grow fast and tolerate cooler weather. Here are the top choices.
Lettuce
Lettuce is a classic fall crop. Choose loose-leaf or romaine varieties for the quickest results. Plant seeds ¼ inch deep, 6 inches apart. Water daily until seedlings emerge. You can start harvesting baby leaves in 30 days. For full heads, wait 50 to 60 days. In Washington, August soil is warm enough for quick germination, but keep the soil moist.
Spinach
Spinach loves cool weather. August planting works well because the soil is still warm, but the nights are cooling down. Sow seeds ½ inch deep, 2 inches apart. Thin seedlings to 4 inches apart once they have two true leaves. Spinach matures in 40 to 50 days. Harvest outer leaves first to extend the season. Avoid planting in full afternoon sun; partial shade is better.
Kale
Kale is incredibly hardy. It can survive light frosts, which actually improve its flavor. Plant seeds ½ inch deep, 12 inches apart. Kale takes 50 to 60 days to mature. You can harvest baby leaves earlier. In Washington, kale planted in August will produce well into November. Choose varieties like Lacinato or Red Russian for best results.
Arugula
Arugula is a fast-growing green with a peppery taste. It is perfect for August planting. Sow seeds ¼ inch deep, 1 inch apart. Thin to 4 inches apart. Arugula matures in just 20 to 30 days. Harvest leaves when they are 3 to 4 inches long. Succession plant every two weeks for a continuous supply.
Root Vegetables For Fall Storage
Root vegetables are another excellent choice for August. They store well and develop sweet flavors after frost. Here are the best options.
Carrots
Carrots need loose, sandy soil to grow straight. Plant seeds ¼ inch deep, 2 inches apart. Keep the soil consistently moist until germination, which can take 10 to 14 days. Carrots mature in 60 to 80 days. In Washington, you can harvest them before the ground freezes. Varieties like ‘Nantes’ or ‘Danvers’ work well.
Beets
Beets are dual-purpose: you can eat the roots and the greens. Plant seeds ½ inch deep, 2 inches apart. Thin seedlings to 4 inches apart. Beets mature in 50 to 60 days. They tolerate light frosts. Harvest when roots are 1 to 2 inches in diameter. ‘Detroit Dark Red’ is a reliable variety.
Turnips
Turnips grow quickly and are very forgiving. Plant seeds ½ inch deep, 4 inches apart. They mature in 40 to 50 days. Both the roots and greens are edible. In Washington, turnips planted in August will be ready before the first hard frost. ‘Purple Top White Globe’ is a common choice.
Radishes
Radishes are the fastest root vegetable. They are ready in 20 to 30 days. Plant seeds ½ inch deep, 1 inch apart. Thin to 2 inches apart. Radishes do not like heat, so August is ideal as temperatures cool. Harvest promptly when roots are 1 inch in diameter. ‘Cherry Belle’ is a classic variety.
Brassicas For Late Season
Brassicas, or cole crops, thrive in cool weather. August planting gives them time to establish before winter.
Broccoli
Broccoli needs consistent moisture and cool temperatures. Plant seeds ¼ inch deep, 18 inches apart. Transplants work better than direct seeding in August. Broccoli takes 60 to 80 days to mature. In Washington, you can harvest heads before heavy frost. ‘Calabrese’ is a good variety.
Cauliflower
Cauliflower is more sensitive than broccoli. It needs even moisture and cool nights. Plant seeds ¼ inch deep, 18 inches apart. Use transplants for best results. Cauliflower matures in 60 to 80 days. Blanch the heads by tying leaves over them. ‘Snowball’ is a reliable variety.
Cabbage
Cabbage is hardy and stores well. Plant seeds ¼ inch deep, 12 inches apart. Transplants are recommended. Cabbage takes 70 to 90 days to mature. In Washington, August-planted cabbage can be harvested in late fall. ‘Early Jersey Wakefield’ is a compact option.
Brussels Sprouts
Brussels sprouts need a long growing season. They are best started in early summer, but you can still plant in August for a late harvest. Plant seeds ½ inch deep, 24 inches apart. They take 90 to 110 days. In Washington, they can survive winter with protection. ‘Long Island Improved’ is a standard variety.
Legumes For Nitrogen Fixing
Legumes add nitrogen to the soil and provide a tasty harvest. They prefer cooler weather.
Peas
Peas are a cool-season crop. August planting works for snap peas and snow peas. Plant seeds 1 inch deep, 2 inches apart. Provide a trellis for support. Peas mature in 55 to 70 days. In Washington, they will produce before frost. ‘Sugar Snap’ is a popular variety.
Fava Beans
Fava beans are very cold-tolerant. They can be planted in August for a fall harvest. Plant seeds 1 inch deep, 6 inches apart. Fava beans take 80 to 100 days. They improve soil structure. Harvest pods when they are plump.
Herbs To Complement Your Garden
Herbs are easy to grow and enhance your cooking. August is a good time to plant them.
Cilantro
Cilantro bolts quickly in heat. August planting in Washington gives it a longer season. Plant seeds ¼ inch deep, 4 inches apart. Harvest leaves regularly. Cilantro matures in 30 to 40 days. Let some plants go to seed for coriander.
Parsley
Parsley is a biennial, but you can harvest it as an annual. Plant seeds ¼ inch deep, 6 inches apart. Soak seeds overnight before planting to speed germination. Parsley takes 70 to 90 days. It tolerates light frost.
Dill
Dill grows quickly. Plant seeds ¼ inch deep, 6 inches apart. It matures in 40 to 50 days. Use fresh leaves or harvest seeds for pickling. Dill self-seeds easily.
Soil Preparation And Watering Tips
Good soil prep is key for August planting. The soil is warm, but it may be dry. Here is how to get it ready.
Amending The Soil
Add compost or aged manure to the soil. This improves drainage and adds nutrients. Mix in 2 to 3 inches of organic matter. Test the soil pH if possible. Most vegetables prefer a pH of 6.0 to 7.0.
Watering Consistently
August can be dry in Washington. Water deeply and regularly. Aim for 1 to 2 inches of water per week. Use drip irrigation or soaker hoses to avoid wetting leaves. Mulch around plants to retain moisture and keep soil cool.
Managing Heat Stress
Even in Washington, August afternoons can be warm. Provide shade for tender seedlings. Use row covers or shade cloth. Water in the morning to reduce evaporation. Watch for signs of wilting.
Succession Planting For Continuous Harvest
Succession planting keeps your garden productive. Plant small batches every two weeks. This ensures a steady supply of fresh vegetables. For example, plant a row of lettuce every 14 days. Do the same for radishes and arugula. This works well in Washington’s mild fall.
Pest And Disease Management
August pests can be active. Watch for aphids, slugs, and cabbage worms. Use insecticidal soap for aphids. Handpick slugs in the evening. Use row covers to protect brassicas from cabbage worms. Rotate crops each year to prevent disease buildup.
Common Pests In Washington
- Aphids: Small, soft-bodied insects. Spray with water or soap.
- Slugs: Active at night. Use beer traps or diatomaceous earth.
- Cabbage worms: Green caterpillars. Use Bt (Bacillus thuringiensis).
- Flea beetles: Small jumping beetles. Use row covers.
Frost Protection Strategies
Washington’s first frost can arrive in October or November. Protect your late-season crops. Use row covers, cloches, or cold frames. Harvest tender vegetables before a hard freeze. Hardy crops like kale and Brussels sprouts can stay in the ground longer.
Extending The Season
Use a cold frame to extend your harvest. Build a simple frame with glass or plastic. Place it over your garden beds. This traps heat and protects from frost. You can grow greens well into December.
Frequently Asked Questions
What Are The Best Vegetables To Plant In August In Washington For Beginners?
Start with radishes, lettuce, and kale. They are easy to grow and mature quickly. These vegetables tolerate Washington’s August conditions well.
Can I Plant Tomatoes In August In Washington?
It is too late for tomatoes. They need warm soil and long days. Focus on cool-season crops instead.
How Do I Protect My August-planted Vegetables From Heat?
Provide shade during the hottest part of the day. Water deeply in the morning. Use mulch to keep soil cool.
What Vegetables Can I Plant In August In Washington For Fall Harvest?
Carrots, beets, broccoli, and spinach are great choices. They mature in 50 to 80 days and tolerate frost.
Do I Need To Fertilize Vegetables Planted In August?
Yes, but use a balanced fertilizer. Apply at planting time and again after four weeks. Avoid high-nitrogen fertilizers for root crops.
Final Tips For Success
Plan your garden layout before planting. Group vegetables with similar water and sun needs. Keep a garden journal to track what works. In Washington, August planting can be very rewarding. You will enjoy fresh vegetables well into autumn. Start small and expand as you gain confidence.
Remember to check your local frost dates. In western Washington, the first frost is usually in November. In eastern Washington, it can be in October. Adjust your planting schedule accordingly. With the right choices, your August garden will thrive.
Happy gardening. You have all the tools you need to succeed. Now get out there and plant those seeds.