
Planting vegetables and herbs in August can extend your growing season and provide a fresh harvest in the fall. However, the types of plants you can grow depend significantly on your USDA Hardiness Zone. This article explores the best vegetables and herbs to plant in August across different hardiness zones, offering tips for successful planting and cultivation.
Understanding Hardiness Zones
The USDA Hardiness Zone map divides North America into 13 zones based on average annual minimum winter temperatures. Knowing your zone helps determine which plants are most likely to thrive in your climate. This guide will cover Zones 3 through 10, as these encompass the majority of the continental United States.
Zone 3 (Minimum Temperatures: -40 to -30°F)
Zone 3 gardeners face short growing seasons and harsh winters. By August, the first frost is just around the corner, so it’s essential to focus on fast-maturing crops and cold-hardy plants.
Vegetables:
- Radishes: Fast-growing and ready to harvest in about 25 days.
- Spinach: Cold-tolerant and can be harvested in about 45 days.
- Turnips: Ready to harvest in 60 days; both roots and greens are edible.
- Kale: Hardy and can withstand frost, maturing in about 55 days.
Herbs:
- Chives: Perennial herb that can survive cold winters.
- Parsley: Cold-tolerant and can continue to grow indoors in pots during winter.
- Cilantro: Fast-growing and can tolerate light frost.
Zone 4 (Minimum Temperatures: -30 to -20°F)
Zone 4 has a slightly longer growing season compared to Zone 3, but frost can still arrive early. Focus on quick-growing and frost-tolerant plants.
Vegetables:
- Lettuce: Varieties like romaine and leaf lettuce mature in about 40-50 days.
- Beets: Harvestable in about 60 days; both roots and greens are edible.
- Broccoli: Cold-hardy and can mature in about 70 days.
- Carrots: Some varieties can mature in 60-75 days.
Herbs:
- Dill: Can handle cooler temperatures and matures quickly.
- Thyme: Perennial herb that can survive frost and cold winters.
- Oregano: Hardy and can be brought indoors to continue growing.
Zone 5 (Minimum Temperatures: -20 to -10°F)
Zone 5 offers a moderate growing season with the possibility of frost by late October. August is an excellent time to plant fall crops.
Vegetables:
- Brussels Sprouts: Take about 90 days to mature and benefit from a light frost.
- Swiss Chard: Tolerates cooler temperatures and can be harvested multiple times.
- Radishes: Fast-growing and can be harvested in about 25 days.
- Cabbage: Cold-tolerant and takes about 70-80 days to mature.
Herbs:
- Sage: Perennial that can withstand frost and grow year-round indoors.
- Marjoram: Less hardy than oregano but can be grown in pots indoors.
- Mint: Hardy perennial that can be invasive; grow in pots to control spread.
Zone 6 (Minimum Temperatures: -10 to 0°F)
Zone 6 offers a longer growing season, making it ideal for a wide variety of fall crops. August is perfect for planting cool-season vegetables.
Vegetables:
- Spinach: Thrives in cooler weather and matures in about 45 days.
- Peas: Plant varieties like snow peas or sugar snap peas for a fall harvest.
- Kale: Hardy and can withstand frost, maturing in about 55 days.
- Collard Greens: Cold-tolerant and take about 75 days to mature.
Herbs:
- Chives: Easy to grow and can survive winter.
- Parsley: Biennial that can grow through the fall and winter in mild climates.
- Lemon Balm: Hardy herb that can withstand light frost.
Zone 7 (Minimum Temperatures: 0 to 10°F)
Zone 7 has a long growing season, allowing for a variety of fall and winter crops. August is a great time to start cool-season vegetables and herbs.
Vegetables:
- Arugula: Quick-growing and ready to harvest in about 30 days.
- Broccoli: Can be planted for a fall harvest and matures in about 70 days.
- Cauliflower: Cold-tolerant and takes about 60-70 days to mature.
- Turnips: Ready to harvest in 60 days; both roots and greens are edible.
Herbs:
- Thyme: Perennial that can grow year-round in mild climates.
- Oregano: Hardy and can be brought indoors to continue growing.
- Rosemary: Tender perennial that can be grown in pots and brought indoors during winter.
Zone 8 (Minimum Temperatures: 10 to 20°F)
Zone 8 offers a long growing season with mild winters, making it possible to grow a wide range of fall and winter crops. August is perfect for starting cool-season vegetables.
Vegetables:
- Lettuce: Plant varieties like romaine and leaf lettuce for a fall harvest.
- Spinach: Thrives in cooler weather and matures in about 45 days.
- Radishes: Fast-growing and can be harvested in about 25 days.
- Beets: Harvestable in about 60 days; both roots and greens are edible.
Herbs:
- Dill: Can handle cooler temperatures and matures quickly.
- Cilantro: Fast-growing and can tolerate light frost.
- Sage: Perennial that can withstand frost and grow year-round indoors.
Zone 9 (Minimum Temperatures: 20 to 30°F)
Zone 9 has a long growing season and mild winters, allowing for a wide variety of crops to be planted in August for fall and winter harvest.
Vegetables:
- Broccoli: Cold-hardy and can mature in about 70 days.
- Carrots: Some varieties can mature in 60-75 days.
- Kale: Hardy and can withstand frost, maturing in about 55 days.
- Swiss Chard: Tolerates cooler temperatures and can be harvested multiple times.
Herbs:
- Basil: Grows well in warm weather but should be harvested before the first frost.
- Parsley: Biennial that can grow through the fall and winter in mild climates.
- Mint: Hardy perennial that can be invasive; grow in pots to control spread.
Zone 10 (Minimum Temperatures: 30 to 40°F)
Zone 10 offers a nearly year-round growing season, making it possible to grow a wide range of vegetables and herbs in August for fall and winter harvest.
Vegetables:
- Lettuce: Plant varieties like romaine and leaf lettuce for a fall harvest.
- Spinach: Thrives in cooler weather and matures in about 45 days.
- Radishes: Fast-growing and can be harvested in about 25 days.
- Peas: Plant varieties like snow peas or sugar snap peas for a fall harvest.
Herbs:
- Dill: Can handle cooler temperatures and matures quickly.
- Cilantro: Fast-growing and can tolerate light frost.
- Thyme: Perennial that can grow year-round in mild climates.
Tips for Successful Planting in August
Regardless of your hardiness zone, following these tips can help ensure a successful fall harvest:
- Soil Preparation: Enrich the soil with compost or organic matter to improve fertility and drainage. Ensure the soil is loose and well-aerated.
- Watering: Consistent watering is crucial, especially during the hot days of August. Water deeply to encourage strong root growth but avoid waterlogging the soil.
- Mulching: Use mulch to retain soil moisture, regulate temperature, and suppress weeds. Organic mulches like straw, grass clippings, or shredded leaves work well.
- Pest Management: Keep an eye out for pests that may still be active in late summer. Use organic pest control methods to protect your plants without harming beneficial insects.
- Frost Protection: Be prepared to protect your plants from early frosts by using row covers, cloches, or cold frames. These can help extend your growing season by a few weeks.
- Succession Planting: To maximize your harvest, consider succession planting. Sow seeds at two-week intervals to ensure a continuous supply of fresh produce.
Conclusion
Planting vegetables and herbs in August can extend your growing season and provide fresh, homegrown produce well into the fall. By understanding your hardiness zone and choosing the right crops, you can make the most of your garden even as summer winds down. With careful planning and proper care, you can enjoy a bountiful harvest and the satisfaction of growing your own food. Happy gardening!

