What to Plant in May: Complete Zone-by-Zone Guide
May is the biggest planting month of the year. Here's exactly what to plant in May for every zone — vegetables, flowers, herbs, trees, and what to avoid. Timely for 2026.
May Planting Quick Reference
| Crop | Start Indoor | Plant Outdoor | Best Zones | Spacing | Days to Harvest |
|---|---|---|---|---|---|
| Tomatoes | Feb–Mar | May (after frost) | 5–8 transplant | 24–36 in | 70–85 days |
| Peppers | Feb–Mar | May (60°F+ soil) | 5–9 transplant | 18–24 in | 60–90 days |
| Cucumbers | Apr (optional) | May (70°F+ soil) | 5–9 direct sow | 36–48 in | 50–65 days |
| Bush Beans | Never | May (60°F+ soil) | 5–10 direct sow | 4–6 in | 50–60 days |
| Zinnias | Apr (optional) | May (after frost) | 5–10 direct sow | 8–12 in | 60–70 days bloom |
| Basil | Mar–Apr | May (70°F+ soil) | 5–10 transplant | 12–18 in | 30–45 days |
| Dahlias | N/A | May (60°F+ soil) | 5–10 tubers | 18–24 in | 90–120 days bloom |
| Sweet Corn | Never | May (65°F+ soil) | 5–9 direct sow | 10–12 in | 65–85 days |
🍅Warm-Season Vegetables to Plant in May
Tomatoes (Transplants Outdoors)
May is prime tomato transplant month for zones 5–8. Wait until nighttime temps consistently stay above 50°F. Set transplants deep — bury 2/3 of the stem for stronger roots. Zones 3–4: wait until late May or early June. Zones 9–10: tomatoes should already be in ground (planted March–April). Stake or cage immediately at planting time.
Peppers & Eggplant
Transplant peppers and eggplant outdoors after all frost danger passes — they need soil temps above 65°F. In zones 5–7, early-to-mid May is typical. Black plastic mulch warms soil 5–10°F faster. Hot peppers need the warmest spot you have. Don't rush these — cold soil stunts them permanently.
Cucumbers, Squash & Melons
Direct sow cucumbers, summer squash, winter squash, and melons in May once soil hits 70°F. These are the most frost-sensitive vegetables — one cold night kills them. In zones 5–6, wait until mid-to-late May. Build small soil mounds (hills) for better drainage and warmth. Succession plant cucumbers every 2 weeks.
Beans & Corn
Direct sow bush beans, pole beans, and sweet corn once soil is 60°F+. Never start beans indoors — they hate transplanting. Plant corn in blocks of at least 4 rows (not single rows) for proper wind pollination. Succession plant bush beans every 2–3 weeks through July for continuous harvest.
Sweet Potatoes
Plant sweet potato slips in May (zones 5–9) once soil is 65°F+. These need a long, hot season — 90–120 days of warm weather. Create raised rows or mounds for warmer soil. In northern zones (5–6), use black plastic mulch to extend the heat season. One of the most productive crops per square foot.
Okra, Southern Peas & Warm-Season Greens
In zones 7–10, May is the time for heat-lovers: okra (soil 65°F+), black-eyed peas, and Malabar spinach (a heat-tolerant spinach substitute). Also direct sow New Zealand spinach — it thrives in heat where regular spinach bolts immediately. These are the crops that love the hottest part of summer.
🌸Flowers to Plant in May
Tender Annual Transplants
After last frost, plant out all tender annuals: zinnias, marigolds, petunias, impatiens, begonias, celosia, cosmos, and calibrachoa. In zones 5–7, mid-May is typically safe. Buy transplants or start from seed indoors 6–8 weeks earlier. Zinnias and cosmos can also be direct sown — they germinate fast in warm soil.
Dahlia Tubers
Plant dahlia tubers in May once soil reaches 60°F. Set tubers 4–6 inches deep, eye (sprout) facing up. Don't water until sprouts emerge — wet dormant tubers rot. Stake tall varieties at planting time (dinner plates need support by July). One of the most rewarding May plantings — blooms July through frost.
Gladiolus & Summer Bulbs
Plant gladiolus corms, canna lilies, elephant ears (Colocasia), caladiums, and tuberous begonias in May. Stagger gladiolus plantings every 2 weeks for continuous cut flowers June–September. Caladiums need soil above 70°F — in zones 5–6, wait until late May. All summer bulbs are frost-tender.
Sunflower Seeds
Direct sow sunflower seeds in May — they germinate in 7–10 days in warm soil. Plant successive batches every 2 weeks for blooms all summer. Giant varieties (Russian Mammoth, 10–12 ft) need full sun and 2 ft spacing. Dwarf varieties (Teddy Bear, Big Smile) work in containers. Kids' favorite garden project.
Perennial Transplants
May is excellent for planting container-grown perennials: coneflower, black-eyed Susan, salvia, daylily, hosta, astilbe, and ornamental grasses. They establish root systems during May's warm, rainy weather and bloom by late summer. Plant on a cloudy day or in evening to reduce transplant shock.
Wildflower Seeds (Warm-Season)
Direct sow warm-season wildflower mixes in May: cosmos, zinnias, rudbeckia, coreopsis, and gaillardia. Rake into bare soil, press firmly, and water gently. No need to cover — most wildflower seeds need light to germinate. May-sown wildflowers bloom by mid-summer and reseed for next year.
🌿Herbs to Plant in May
Basil (All Types)
Basil is THE May herb — plant transplants or direct sow after all frost danger. Soil must be 70°F+. Sweet basil, Thai basil, purple basil, lemon basil — all go out in May. Pinch growing tips when plants reach 6 inches to encourage bushy growth. Basil and tomatoes go in the ground the same week.
Warm-Season Herbs
May is planting time for heat-loving herbs: cilantro (quick succession — bolts fast in heat), dill (direct sow), parsley (transplants), chives (transplants or divisions), oregano, thyme, and sage. In zones 8–10, cilantro may already be bolting — switch to culantro (Eryngium foetidum) which handles heat.
Rosemary, Lavender & Mediterranean Herbs
Transplant rosemary, lavender, and other Mediterranean herbs in May. These need excellent drainage — amend clay soil with sand or plant in raised beds. Full sun, lean soil, minimal water once established. In zones 5–6, treat rosemary as annual or overwinter indoors. Lavender needs alkaline soil (add lime if acidic).
Mint & Lemon Balm (Contained)
Plant mint and lemon balm in May — but ALWAYS in containers. Both spread aggressively via underground runners. A single mint plant can colonize 10 sq ft in one season. Sink a bottomless pot into the garden bed to contain roots, or grow exclusively in pots. Spearmint, peppermint, chocolate mint, mojito mint — all prolific.
🌳Trees, Shrubs & Perennials for May
Container-Grown Trees & Shrubs
May is one of the best months to plant container-grown trees and shrubs — warm soil promotes root growth, and spring rains help establishment. Plant hydrangeas, roses, crape myrtles, butterfly bush, and flowering shrubs. Dig the hole 2–3x wider than the root ball but no deeper. Mulch 3 inches, keep off trunk.
Rose Bushes
May is peak rose planting month for container-grown roses in zones 5–8. Knock Out roses, David Austin, climbing roses, and hybrid teas all establish well from May transplants. Soak root ball before planting. Position bud union at soil level (north) or 2 inches below (south). First-year roses need 1 inch water per week.
Ornamental Grasses
Transplant ornamental grasses in May — they establish quickly in warm soil. Miscanthus, switchgrass, fountain grass, Karl Foerster, muhly grass, and blue fescue all thrive from May planting. Most reach full size by September. Space according to mature width, not nursery pot size — they expand significantly.
Groundcovers & Vines
May's warmth and moisture make it ideal for establishing groundcovers: creeping thyme, sedum, ajuga, vinca minor, pachysandra, and sweet woodruff. Also plant climbing vines: clematis, honeysuckle, trumpet vine, and climbing hydrangea. Install supports at planting time — don't wait until vines are flopping.
Native Plant Installations
May is prime for native plant gardens: plant native perennials, grasses, and shrubs from local nurseries. Native plants establish faster in spring when soil biology is most active. Purple coneflower, wild bergamot, little bluestem, switchgrass, and native asters planted in May will be established by fall.
🗺️Zone-Specific May Planting Guide
Zones 3–4 (Northern US & Canada)
Last frost: mid-to-late May. Early May: continue indoor starts (tomatoes, peppers). Mid-May: direct sow peas, lettuce, spinach, radishes, carrots outdoors. Late May: transplant hardy vegetables (broccoli, cabbage, kale). Wait until early June for frost-tender crops. Soil may still be cold — check with thermometer before planting warm-season crops.
Zones 5–6 (Upper Midwest, Northeast)
Last frost: early-to-mid May. Early May: plant potatoes, onion sets, cool-season crops outdoors. Mid-May (after last frost): transplant tomatoes, peppers, basil. Late May: direct sow beans, corn, cucumbers, squash. This is the busiest planting month — most of the garden goes in during May.
Zones 7–8 (Mid-Atlantic, Southeast, Pacific NW)
Last frost: mid-April (already passed). May is full warm-season planting: all tomatoes, peppers, squash, melons, okra, sweet potatoes, all tender annuals. Succession plant lettuce in shade (bolt-resistant varieties). Start thinking about summer heat — install drip irrigation and mulch heavily.
Zones 9–10 (Deep South, Desert SW, So. California)
May: warm-season crops well underway. Plant heat-tolerant varieties: Malabar spinach, yard-long beans, sweet potatoes, okra, Southern peas. In desert zones, shade cloth may be needed for tomatoes (over 95°F reduces fruit set). Focus on heat-tolerant flowers: lantana, vinca, portulaca, zinnia. Water deeply and mulch.
Zone 11 (Tropical Florida, Hawaii)
May begins the wet season in tropical zones. Plant tropical fruits: papaya, banana, mango. Continue warm-season vegetables: cherry tomatoes (heat-tolerant varieties), peppers, herbs. Prepare for hurricane season — stake tall plants, ensure drainage. Focus on quick-maturing crops that can harvest before peak storm season.
⚠️What NOT to Plant in May
Cool-Season Crops in Warm Zones
Don't plant lettuce, spinach, peas, or broccoli outdoors in zones 7+ in May — they'll bolt (go to seed) immediately in the heat. In zones 5–6, you can still plant these in early May but expect them to finish by mid-June. Switch to heat-tolerant alternatives: Malabar spinach, New Zealand spinach, and Swiss chard.
Spring Bulbs (Too Late)
Don't plant tulips, daffodils, alliums, or crocus in May — spring-blooming bulbs need fall planting (October–November) to vernalize. If you missed fall planting, buy potted bulbs in bloom from nurseries for instant impact. Plan to plant bulbs this coming October instead.
Bare-Root Plants (Season Over)
May is too late for bare-root trees, roses, and perennials — the bare-root planting window is February–April while plants are dormant. If you missed it, buy container-grown plants instead (they transplant fine in May). Bare-root planted now will struggle with leaf emergence before root establishment.
Frost-Tender Crops Before Last Frost
In zones 3–5, don't rush tender crops outdoors before your last frost date. One late frost kills tomatoes, peppers, basil, and all tender annuals. Check 10-day forecast before transplanting. Have row cover or frost cloth ready for unexpected cold snaps even after the average last frost date.
Visualize Your May Garden
Upload a photo of your yard and see what your May plantings will look like in all four seasons — with cost estimates, plant lists, and a contractor-ready PDF.
Design My Garden →Frequently Asked Questions
Is May too late to start a garden?
Not at all — May is actually the most important planting month for most of the US. Zones 5–8 plant the majority of their garden in May. Even in zones 3–4, late May is when the growing season truly begins. The only things 'too late' for May are spring bulbs (need fall planting) and bare-root plants (need dormant-season planting).
Can I direct sow tomatoes in May?
You can, but you'll be 4–6 weeks behind transplants. Direct-sown tomatoes in May won't fruit until late August in most zones. For best results, buy transplants or start seeds indoors in February–March. If you must direct sow, choose determinate varieties with shorter days-to-maturity (50–65 days).
What if there's a late frost after I plant?
Have frost cloth, old sheets, or row cover ready. Cover tender plants if nighttime temps drop below 35°F. Don't use plastic directly on plants — it transfers cold. Wall-of-water protectors work well for tomatoes. Check 10-day forecasts religiously in early May, especially in zones 5–6.
How do I know when soil is warm enough?
Use a soil thermometer inserted 4 inches deep. Take readings in morning (coldest point). Beans and corn need 60°F, tomatoes and peppers 65°F, cucumbers and melons 70°F. Without a thermometer, wait 2 weeks after your last frost date — soil usually catches up by then.
Should I fertilize at planting time in May?
Use a balanced starter fertilizer (10-10-10) or compost at planting time. Avoid high-nitrogen fertilizer on tomatoes and peppers until they set fruit — too much nitrogen produces leaves instead of flowers. Side-dress with compost or balanced fertilizer 4–6 weeks after transplanting.
What flowers bloom fastest if I plant in May?
Fastest May-planted flowers: zinnias (60 days), marigolds (50 days), sunflowers (55–70 days), cosmos (60 days), and nasturtiums (45 days). All can be direct sown in May and will bloom by mid-to-late July. For instant color, buy annuals in bloom from nurseries.