Hardiness zone 7’s moderate climate allows arugula to be planted as soon as the ground becomes workable. The best time to plant arugula in hardiness zone 7 is early spring, typically from mid-March to early April, as soon as the soil can be worked. This timing gives you a head start on a cool-season crop that thrives in temperatures between 45°F and 65°F.
Arugula is a fast-growing leafy green that loves cool weather. In zone 7, you have two main planting windows: spring and fall. Spring planting lets you harvest before summer heat turns the leaves bitter. Fall planting gives you a second crop that can last into early winter with some protection.
Understanding your local frost dates helps you plan. Zone 7’s last spring frost usually occurs between late March and mid-April. Your first fall frost hits around mid-October to early November. These dates guide when to sow seeds or set out transplants.
Understanding Hardiness Zone 7 Climate For Arugula
Zone 7 covers a wide area across the United States, from the Mid-Atlantic to the Pacific Northwest. Average minimum winter temperatures range from 0°F to 10°F. Summers can get hot, with temperatures often reaching the 90s. This heat is arugula’s enemy—it triggers bolting, where the plant flowers and turns bitter.
Arugula grows best in cool, moist conditions. In zone 7, you can plant it in early spring and again in late summer for a fall harvest. The key is to avoid the hottest months of July and August. Even with shade cloth, summer arugula often fails.
Your soil temperature matters more than air temperature. Arugula seeds germinate best when soil is between 40°F and 55°F. Use a soil thermometer to check. If the soil is too cold, seeds rot. If too warm, germination drops.
Best Time To Plant Arugula In Hardiness Zone 7
Spring Planting Window
Start your spring planting as soon as the ground thaws and is dry enough to work. In zone 7, this is typically mid-March. You can even plant arugula under row covers or in a cold frame two weeks earlier. The seeds tolerate light frosts and temperatures down to 25°F.
For a continuous harvest, sow seeds every 2 to 3 weeks until late April. This succession planting ensures you have tender leaves all spring. Stop planting by early May, as the heat of late spring will cause bolting.
Here is a simple spring planting schedule for zone 7:
- Mid-March: First sowing, use row covers if frost is heavy
- Late March: Second sowing, soil should be workable
- Early April: Third sowing, ideal soil temperatures
- Mid-April: Fourth sowing, last reliable spring window
- Late April: Final spring sowing, choose bolt-resistant varieties
Fall Planting Window
Fall is actually the best season for arugula in zone 7. The cooler temperatures and shorter days produce the sweetest, most tender leaves. Start your fall planting in late August to early September. Count back 4 to 6 weeks from your first expected frost date.
For a fall harvest, sow seeds directly in the garden from mid-August through mid-September. You can continue planting into early October if you use cold frames or row covers. Arugula matures in 30 to 40 days, so timing is flexible.
Fall planting tips for zone 7:
- Choose a spot that gets afternoon shade to reduce heat stress
- Water deeply after sowing to cool the soil
- Thin seedlings to 4 inches apart for good air flow
- Mulch around plants to keep soil moist and cool
- Cover with row covers when night temperatures drop below 25°F
Winter Planting With Protection
In zone 7, you can grow arugula through winter with some protection. Use a cold frame, low tunnel, or heavy row cover. Plant in late September to early October. The plants will grow slowly but provide fresh greens all winter.
Choose winter-hardy varieties like ‘Astro’ or ‘Sylvetta’. These tolerate colder temperatures better than standard arugula. With a cold frame, you can harvest from November through February. Just open the cover on sunny days to prevent overheating.
Factors That Affect Planting Time
Soil Temperature
Soil temperature is the most critical factor for arugula germination. Seeds need soil between 40°F and 55°F for best results. If soil is below 40°F, seeds may rot. Above 60°F, germination rates drop sharply.
Use a soil thermometer to check at 2 inches deep. In zone 7, soil reaches 40°F by mid-March in most areas. Sandy soils warm faster than clay soils. Raised beds also warm up earlier in spring.
Day Length
Arugula is sensitive to day length. Long days (over 14 hours) trigger bolting. In zone 7, days start getting longer after the spring equinox in March. By late May, days are long enough to cause bolting, even if temperatures are still cool.
Fall planting benefits from shortening days. Shorter days keep arugula in vegetative growth longer. This is why fall arugula often tastes better and lasts longer than spring crops.
Variety Selection
Different arugula varieties have different heat tolerance. Standard arugula (Eruca sativa) bolts quickly in heat. Wild arugula (Diplotaxis tenuifolia) is more heat-tolerant and can be planted later in spring.
For spring planting in zone 7, choose bolt-resistant varieties like ‘Astro’ or ‘Apollo’. For fall, any variety works well. For winter, choose cold-hardy types like ‘Sylvetta’ or ‘Wasabi arugula’.
Step-By-Step Planting Guide For Zone 7
Preparing The Soil
Arugula grows best in well-drained soil rich in organic matter. Before planting, amend your soil with compost or aged manure. Work it in to a depth of 6 to 8 inches. Arugula prefers a soil pH between 6.0 and 7.0.
Test your soil pH with a simple kit from a garden center. If pH is too low, add lime. If too high, add sulfur. Arugula is not too picky, but proper pH helps nutrient uptake.
Sowing Seeds
Sow arugula seeds 1/4 inch deep and 1 inch apart in rows. Space rows 12 to 18 inches apart. You can also broadcast seeds in a bed and thin later. Cover seeds lightly with soil and water gently.
Germination takes 5 to 10 days at optimal soil temperatures. Keep the soil moist but not waterlogged. Use a fine mist to avoid washing seeds away. Once seedlings emerge, thin them to 4 to 6 inches apart.
Watering And Care
Arugula needs consistent moisture for tender leaves. Water deeply once or twice a week, depending on rainfall. In hot weather, water more frequently. Mulch with straw or shredded leaves to retain moisture and keep soil cool.
Fertilize lightly with a balanced organic fertilizer every 3 to 4 weeks. Too much nitrogen can make leaves tough. A side dressing of compost tea works well. Watch for flea beetles, which love arugula. Use row covers to protect young plants.
Harvesting
You can start harvesting arugula when leaves are 3 to 4 inches long, usually 30 to 40 days after sowing. Pick outer leaves first, leaving the inner rosette to continue growing. This cut-and-come-again method extends your harvest.
For the best flavor, harvest in the morning when leaves are crisp. Rinse and dry leaves immediately. Store in a plastic bag in the refrigerator for up to 5 days. Do not wash until ready to use.
Common Mistakes To Avoid
- Planting too late in spring: Leads to bolting and bitter leaves
- Planting too early in fall: Heat stress reduces germination
- Overcrowding: Causes poor air flow and disease
- Underwatering: Makes leaves tough and bitter
- Ignoring pests: Flea beetles can destroy young plants
- Not using succession planting: Limits harvest window
Extending The Growing Season
Using Row Covers
Row covers are lightweight fabric that protect plants from frost and pests. In zone 7, you can plant arugula 2 weeks earlier in spring with row covers. They also extend fall harvest by 4 to 6 weeks. Use floating row covers that let light and water through.
Cold Frames
A cold frame is a box with a glass or plastic top that traps heat. In zone 7, a cold frame lets you grow arugula all winter. Plant in late September, and you can harvest through February. Open the lid on sunny days to prevent overheating.
Shade Cloth
In late spring, shade cloth can delay bolting. Use 30% to 50% shade cloth over arugula beds. This reduces temperature and light intensity. It can extend your spring harvest by 2 to 3 weeks.
Frequently Asked Questions
Can I plant arugula in summer in zone 7?
Summer planting is not recommended. High temperatures cause bolting and bitter leaves. If you try, use shade cloth and choose heat-tolerant varieties. Even then, success is limited.
What is the latest I can plant arugula in fall in zone 7?
You can plant as late as early October if you use row covers or a cold frame. Without protection, plant by mid-September to ensure harvest before hard frost.
Should I start arugula indoors or direct sow?
Direct sowing is best. Arugula has a taproot that does not transplant well. If you start indoors, use biodegradable pots and transplant carefully without disturbing roots.
How often should I water arugula in zone 7?
Water deeply once or twice a week. In hot, dry periods, water every 2 to 3 days. Keep soil consistently moist but not soggy. Mulch helps retain moisture.
Can I grow arugula in containers in zone 7?
Yes, containers work well. Use pots at least 6 inches deep with drainage holes. Place in a spot that gets morning sun and afternoon shade. Water more frequently than garden beds.
Conclusion
The best time to plant arugula in hardiness zone 7 is early spring and again in late summer for fall harvest. Spring planting starts in mid-March, as soon as soil is workable. Fall planting begins in late August. With protection like row covers or cold frames, you can extend your harvest into winter.
Focus on soil temperature, not just air temperature. Keep soil between 40°F and 55°F for germination. Use succession planting for a continuous supply. Avoid summer heat by planting in spring and fall only.
With these guidelines, you can enjoy fresh, peppery arugula from your zone 7 garden for most of the year. Start with a small patch, learn your microclimate, and adjust your planting dates accordingly. Happy growing.