As summer's heat begins to wane and the days start to shorten, August presents a perfect opportunity to transition your garden from summer's bounty to fall's harvest. For gardeners who want to extend their growing season and enjoy fresh produce well into the cooler months, now is the time to start planting cool-season crops. Here are some of the best cool-season plants to sow in August and tips to ensure a successful fall garden.

Why Plant Cool-Season Crops in August?

Cool-season crops thrive in the cooler temperatures of fall and early winter. By planting these crops in August, you give them a head start before the first frost hits, ensuring they have enough time to mature. Many of these plants are hardy and can withstand light frosts, allowing for a prolonged harvest period.

Top Cool-Season Crops to Plant in August

1. Leafy Greens

• Lettuce: Varieties like butterhead, romaine, and leaf lettuce are perfect for August planting. They grow quickly and can be harvested in just a few weeks.
• Spinach: Spinach thrives in cool weather, making it an excellent choice for late-summer planting. Look for fast-growing varieties to maximize your harvest.
• Kale: This nutrient-packed green not only tolerates frost but also becomes sweeter after exposure to cold weather. Curly, Lacinato, and Red Russian are popular choices.
• Arugula: Known for its peppery flavor, arugula grows quickly and can be harvested multiple times. Plant every couple of weeks for a continuous supply.

LettucePhoto byRobin Phelps/Sow Many Plants

2. Root Vegetables

• Carrots: Shorter varieties like 'Nantes' are ideal for fall planting. Carrots taste sweeter when harvested after the first frost.
• Beets: Beets are dual-purpose crops, providing both tender greens and sweet roots. Plant in well-drained soil for the best results.
• Radishes: Radishes are one of the fastest-growing crops, ready to harvest in as little as 3-4 weeks. Plant them in succession for a steady supply.
• Turnips: Both turnip greens and roots are edible and delicious. Plant them now for a harvest in about two months.

carrotsPhoto byRobin Phelps/Sow Many Plants

3. Brassicas

• Broccoli: Start broccoli indoors or in a shaded area before transplanting to your garden. It prefers cooler weather and will produce well into the fall.
• Cauliflower: Like broccoli, cauliflower benefits from starting indoors. Ensure consistent watering and cooler temperatures for a successful harvest.
• Cabbage: Cabbage is a hardy vegetable that can withstand frost, making it a great candidate for fall planting. Varieties like 'Savoy' and 'Red Acre' are particularly good for cooler weather.

BroccoliPhoto byRobin Phelps/Sow Many Plants

4. Alliums

• Leeks: Leeks are a long-season crop, so planting in August will give them enough time to grow large before winter. They can be harvested throughout the winter as needed.
• Onions: Start with onion sets or seeds for a fall harvest. Varieties like 'White Lisbon' are ideal for cooler temperatures.

OnionsPhoto byRobin Phelps/Sow Many Plants

5. Herbs

• Cilantro: Cilantro tends to bolt in the heat, so August is an ideal time to plant it for a continuous supply throughout the fall.
• Parsley: Parsley is a biennial herb that does well in cooler weather. It’s frost-tolerant and can be harvested throughout the fall and early winter.
• Chives: Chives are a hardy perennial herb that can be planted in August for use in fall and winter cooking.

ParsleyPhoto byRobin Phelps/Sow Many Plants

Tips for a Successful August Garden

• Soil Preparation: Ensure your soil is well-drained and rich in organic matter. Adding compost can help retain moisture and provide essential nutrients.
• Watering: Cooler weather reduces evaporation, but consistent watering is still crucial. Keep the soil evenly moist, especially during seed germination.
• Mulching: Mulch around plants to conserve moisture, reduce weeds, and protect roots from temperature fluctuations.
• Pest Control: As the weather cools, some pests become less active, but remain vigilant. Use row covers to protect young plants from insects and frost.
• Succession Planting: For a continuous harvest, plant crops like lettuce, radishes, and spinach in intervals of 2-3 weeks.
• Frost Protection: Be prepared for early frosts by having row covers or cold frames ready. These will extend your growing season and protect tender plants.

August is an exciting time in the garden, offering a chance to plant cool-season crops that will thrive as the weather cools. By choosing the right plants and following these tips, you can enjoy a bountiful harvest long after summer's end.

Happy planting!

Edward C. Smith, The Vegetable Gardener's Bible, Storey Publishing, 2009