New Hampshire’s cool August nights make it ideal for planting lettuce, arugula, and other greens that bolt in heat. When you are looking for the Best Vegetables To Plant In August In New Hampshire, you need to focus on crops that thrive in shortening days and cooler temperatures. This guide will walk you through the top choices, planting tips, and care strategies for a productive fall harvest.
August in New Hampshire brings a unique gardening window. The intense summer heat fades, and the soil remains warm, which speeds up germination. You can still enjoy fresh produce well into October and November with the right selections.
Why August Planting Works In New Hampshire
August is not too late to start a vegetable garden in New Hampshire. The key is choosing fast-maturing varieties that can handle light frosts. Many vegetables actually taste better after a touch of frost, as it converts starches into sugars.
The average first frost in New Hampshire ranges from late September in the north to mid-October in the south. This gives you 60 to 90 days of growing time, depending on your location. You can maximize this window by selecting crops with short days to maturity.
Understanding Your Growing Zone
New Hampshire spans USDA hardiness zones 3b to 6a. Northern areas have shorter seasons, so you need to be more selective. Southern zones offer a bit more flexibility with later frost dates.
- Zone 3b-4a: Northern NH, first frost around September 15-25
- Zone 4b-5a: Central NH, first frost around September 25-October 5
- Zone 5b-6a: Southern NH, first frost around October 5-15
Best Vegetables To Plant In August In New Hampshire
This section covers the top performers for late-summer planting. Each vegetable is chosen for its cold tolerance, quick maturity, and ability to handle New Hampshire’s unpredictable weather.
Leafy Greens: The August Champions
Leafy greens are the easiest and most reliable crops for August planting. They grow quickly and can be harvested as baby greens in just 30 days.
Lettuce
Lettuce loves cool nights. Choose loose-leaf or romaine varieties for the best results. Head lettuce takes too long and may not mature before frost.
- Recommended varieties: ‘Black Seeded Simpson’, ‘Red Sails’, ‘Buttercrunch’
- Days to maturity: 45-60 days
- Planting depth: 1/4 inch
- Spacing: 6-8 inches apart
Spinach
Spinach is a cold-hardy superstar. It can survive temperatures down to 20°F with some protection. August planting gives you a fall crop that tastes sweeter than spring spinach.
- Recommended varieties: ‘Bloomsdale’, ‘Space’, ‘Tyee’
- Days to maturity: 40-50 days
- Planting depth: 1/2 inch
- Spacing: 3-4 inches apart
Arugula
Arugula bolts quickly in summer heat, but August’s cooler nights keep it tender and peppery. You can harvest leaves in as little as 20 days.
- Recommended varieties: ‘Astro’, ‘Rocket’
- Days to maturity: 20-40 days
- Planting depth: 1/4 inch
- Spacing: 2-3 inches apart
Kale
Kale is extremely frost-tolerant and actually improves in flavor after a freeze. It is one of the most reliable fall vegetables in New Hampshire.
- Recommended varieties: ‘Winterbor’, ‘Lacinato’, ‘Red Russian’
- Days to maturity: 50-60 days
- Planting depth: 1/2 inch
- Spacing: 12-18 inches apart
Swiss Chard
Swiss chard handles light frosts well and produces colorful stems that brighten the garden. It is slower than other greens but worth the wait.
- Recommended varieties: ‘Bright Lights’, ‘Fordhook Giant’
- Days to maturity: 50-60 days
- Planting depth: 1/2 inch
- Spacing: 8-12 inches apart
Root Vegetables: Underground Treasures
Root vegetables store well and develop sweetness as temperatures drop. They are perfect for August planting because they mature underground, protected from early frosts.
Carrots
Carrots need consistent moisture to germinate. August rains often help with this. Choose shorter varieties for heavier New Hampshire soils.
- Recommended varieties: ‘Nantes’, ‘Danvers’, ‘Paris Market’
- Days to maturity: 50-70 days
- Planting depth: 1/4 inch
- Spacing: 2-3 inches apart
Beets
Beets are dual-purpose: you can eat the roots and the greens. They germinate quickly in warm August soil and grow well into fall.
- Recommended varieties: ‘Detroit Dark Red’, ‘Golden’, ‘Chioggia’
- Days to maturity: 50-60 days
- Planting depth: 1/2 inch
- Spacing: 3-4 inches apart
Radishes
Radishes are the fastest crop you can plant. Some varieties are ready in just 25 days. They are perfect for filling gaps in the garden.
- Recommended varieties: ‘Cherry Belle’, ‘French Breakfast’, ‘Easter Egg’
- Days to maturity: 25-35 days
- Planting depth: 1/2 inch
- Spacing: 1-2 inches apart
Turnips
Turnips are underrated in New Hampshire gardens. They grow quickly and the greens are edible too. Frost improves their flavor.
- Recommended varieties: ‘Purple Top White Globe’, ‘Hakurei’
- Days to maturity: 45-60 days
- Planting depth: 1/2 inch
- Spacing: 4-6 inches apart
Parsnips
Parsnips take longer to mature but are worth the wait. They need a full 100-120 days, so plant them in early August in southern NH only.
- Recommended varieties: ‘Hollow Crown’, ‘Harris Model’
- Days to maturity: 100-120 days
- Planting depth: 1/2 inch
- Spacing: 3-4 inches apart
Brassicas: Cold Weather Favorites
Brassicas, or cole crops, thrive in cool weather. They can handle light frosts and even improve in flavor after cold exposure.
Broccoli
Fall broccoli often produces better heads than spring-planted crops. The cool weather prevents premature flowering.
- Recommended varieties: ‘Green Goliath’, ‘Waltham 29’, ‘De Cicco’
- Days to maturity: 55-70 days
- Planting depth: 1/4 inch (start indoors) or transplant
- Spacing: 18-24 inches apart
Cauliflower
Cauliflower is trickier but rewarding. Choose fast-maturing varieties and protect heads from sunscald by tying leaves over them.
- Recommended varieties: ‘Snow Crown’, ‘Amazing’
- Days to maturity: 55-65 days
- Planting depth: 1/4 inch (start indoors) or transplant
- Spacing: 18-24 inches apart
Cabbage
Cabbage stores well and can be harvested after frost. It is a staple for fall gardens in New Hampshire.
- Recommended varieties: ‘Early Jersey Wakefield’, ‘Stonehead’
- Days to maturity: 60-70 days
- Planting depth: 1/4 inch (start indoors) or transplant
- Spacing: 12-18 inches apart
Brussels Sprouts
Brussels sprouts need a long season but are extremely cold-tolerant. Plant them in early August in southern NH for a late fall harvest.
- Recommended varieties: ‘Long Island Improved’, ‘Jade Cross’
- Days to maturity: 90-100 days
- Planting depth: 1/4 inch (start indoors) or transplant
- Spacing: 18-24 inches apart
Peas And Beans: Quick Legumes
Peas and beans can still be planted in August, but choose varieties with short maturity times. They add nitrogen to the soil for next year.
Snow Peas And Snap Peas
Peas love cool weather. Plant them in early August for a harvest before hard frost. They need support for best growth.
- Recommended varieties: ‘Sugar Ann’, ‘Oregon Sugar Pod II’
- Days to maturity: 55-65 days
- Planting depth: 1 inch
- Spacing: 2-3 inches apart
Bush Beans
Bush beans mature faster than pole beans. Plant them in early August for a late-season harvest. They are less prone to disease in cooler weather.
- Recommended varieties: ‘Provider’, ‘Contender’
- Days to maturity: 50-55 days
- Planting depth: 1 inch
- Spacing: 3-4 inches apart
How To Prepare Your Garden For August Planting
August soil is warm and dry, which is good for germination but can be challenging for moisture retention. Follow these steps to set your fall garden up for success.
Clear Out Summer Crops
Remove spent tomato, pepper, and squash plants that are no longer producing. Pull out weeds and debris to reduce pest and disease pressure.
Amend The Soil
Summer crops deplete nutrients. Add a 1-inch layer of compost or well-rotted manure. Work it into the top 4-6 inches of soil. This provides slow-release nutrients for fall crops.
Water Deeply Before Planting
August heat can dry out soil quickly. Water the bed thoroughly a day before planting. This ensures seeds have consistent moisture for germination.
Use Shade Cloth If Needed
If a heat wave hits after planting, use shade cloth to protect young seedlings. Remove it once temperatures moderate. This prevents bolting in greens.
Plant Successionally
Stagger your plantings every 2-3 weeks. This gives you a continuous harvest rather than a single glut. For example, plant radishes every 10 days.
Care Tips For August-Planted Vegetables
Fall gardens need different care than spring gardens. Here are specific strategies for New Hampshire’s late-season conditions.
Watering In Late Summer
August can still be hot and dry. Water deeply once or twice a week, depending on rainfall. Aim for 1 inch of water per week. Mulch around plants to retain moisture and keep soil cool.
Fertilizing For Fall Growth
Use a balanced, water-soluble fertilizer every 2-3 weeks. Liquid fish emulsion or seaweed extract works well. Avoid high-nitrogen fertilizers that promote leafy growth at the expense of roots.
Pest Management
Fall pests include aphids, cabbage worms, and slugs. Use row covers to protect brassicas from cabbage moths. Hand-pick slugs in the evening. Insecticidal soap works for aphids.
Frost Protection
Keep row covers, cloches, or old sheets handy for unexpected frosts. Hardy crops like kale and spinach can handle light frosts without protection. Tender greens may need covering.
Extending The Season
Use cold frames or low tunnels to extend your harvest by 4-6 weeks. These structures trap heat and protect plants from hard frosts. You can build simple ones from PVC pipes and clear plastic.
Common Mistakes To Avoid
Even experienced gardeners make mistakes with August planting. Here are the most common pitfalls and how to avoid them.
- Planting too late: Check your first frost date and count backward from the days to maturity. Add 2 weeks for slower growth in shorter days.
- Overcrowding: Fall crops need space to grow. Thin seedlings to recommended spacing. Crowded plants are more prone to disease.
- Ignoring soil moisture: August heat dries out soil fast. Check moisture daily, especially for shallow-rooted greens.
- Forgetting to harden off transplants: If you start seeds indoors, gradually expose them to outdoor conditions over 5-7 days before planting.
- Planting heat-loving crops: Tomatoes, peppers, and eggplants will not mature before frost. Stick to cool-season vegetables.
Harvesting And Storing Fall Vegetables
Knowing when and how to harvest extends the usability of your crops. Here are guidelines for each type.
Leafy Greens
Harvest outer leaves when they reach 4-6 inches tall. Leave the inner leaves to continue growing. You can cut entire heads of lettuce at the base. Store greens in a plastic bag in the refrigerator for up to 2 weeks.
Root Vegetables
Harvest carrots and beets when they reach full size. Leave parsnips in the ground until after a hard frost for sweetness. Store roots in a cool, dark place in damp sand or sawdust.
Brassicas
Harvest broccoli heads before the flowers open. Cut cabbage heads when they feel firm. Brussels sprouts improve after frost; harvest from the bottom up. Store in the refrigerator or a root cellar.
Peas And Beans
Harvest snow peas when pods are flat. Pick snap peas when pods are plump. Harvest bush beans when pods are slender and snap easily. Store in the refrigerator for up to a week.
FAQ: Best Vegetables To Plant In August In New Hampshire
Can I plant tomatoes in August in New Hampshire?
No, tomatoes are warm-season crops that need 60-80 days to mature. They will not produce before frost. Focus on cool-season vegetables instead.
What is the fastest vegetable to plant in August?
Radishes are the fastest, ready in 25-30 days. Arugula and baby lettuce can be harvested in 20-30 days. These are ideal for quick results.
Do I need to start seeds indoors for August planting?
For most crops, direct sowing works fine. For slow-growing brassicas like Brussels sprouts or broccoli, starting seeds indoors 4-6 weeks before planting can give you a head start.
How do I protect my August garden from early frost?
Use row covers, cloches, or cold frames. Water the soil before a frost, as moist soil retains heat. Hardy crops like kale and spinach can survive light frosts without protection.
Can I plant garlic in August in New Hampshire?
No, garlic is planted in the fall, typically October, for harvest the next summer. August is too early. Focus on quick-maturing fall crops instead.
Final Thoughts On August Planting In New Hampshire
August is a productive month for New Hampshire gardeners. The key is choosing the right crops and managing moisture and frost. Leafy greens, root vegetables, and brassicas are your best bets. With a little planning, you can enjoy fresh vegetables well into November.
Start by clearing out summer debris, amending the soil, and planting fast-maturing varieties. Water consistently and protect from pests. Use row covers or cold frames to extend the season. Your fall garden will reward you with crisp, sweet vegetables that taste better than anything from the store.
Remember to check your specific frost dates and adjust planting times accordingly. Northern gardeners need to be more aggressive with early planting, while southern gardeners have a bit more leeway. Either way, August is not too late to start a garden in New Hampshire.
So get out there, prepare your beds, and plant those seeds. Your taste buds will thank you when you are eating fresh salads and roasted root vegetables in October.