May is the month the garden fills up. The frost risk is over in Zone 8, the soil is warm, and almost everything can go outside. May is for planting warm-season crops in earnest, succession sowing, and harvesting the last of the spring crops before the heat takes over.
What May means in Zone 8
USDA Zone 8 runs through the southern United States, from parts of Texas, Louisiana, Georgia and South Carolina to the Pacific Northwest coast and parts of California. Winters are mild, with average winter lows of 10 to 20°F, and the growing season is long, which gives Zone 8 gardeners one of the most forgiving calendars in the country.
The dates that matter most are the frost averages. The average last spring frost in Zone 8 is Mar 1–15, and the average first autumn frost is Nov 15–Dec 1. These are USDA zone averages drawn from NOAA frost records, not exact dates for any one garden. Always check your local extension service and the forecast before planting tender crops outside. Use our frost date calculator for your zone’s averages.
May in Zone 8 is the last month for spring crops and the first month for fall planning: peas and lettuce are finishing, while fall brassicas started indoors now will be ready for the autumn garden. Mulch everything before the summer heat arrives, because dry May soil turns to dust fast.
May task list
- Plant beans, corn, squash, cucumbers, okra and sweet potato slips.
- Succession-sow lettuce, radishes, carrots and beans every two weeks.
- Start fall brassicas indoors late in the month.
- Mulch everything, feed tomatoes, and set up supports for beans and tomatoes.
- Harvest spring crops: peas, lettuce, spinach, carrots and broccoli.
- Water deeply in dry spells and weed little and often.
- Plant out herbs and flowers to attract pollinators.
What to start indoors in May
Start these under cover now, with strong light and steady moisture.
- Broccoli — matures in 60–85 days; frost-tolerant; soil pH 6.0–7.0.
- Cabbage — matures in 60–90 days; frost-tolerant; soil pH 6.0–7.0.
- Kale — matures in 50–65 days; hardy; soil pH 6.0–7.5.
- Cauliflower — matures in 55–80 days; frost-tolerant; soil pH 6.0–7.0.
What to direct-sow in May
Sow these straight into prepared beds and water the seed row well.
- Green beans — matures in 50–65 days; tender; soil pH 6.0–7.0.
- Sweet corn — matures in 60–90 days; tender; soil pH 6.0–6.8.
- Zucchini — matures in 45–55 days; tender; soil pH 6.0–7.5.
- Cucumbers — matures in 50–70 days; tender; soil pH 6.0–7.0.
- Okra — matures in 50–65 days; tender; soil pH 6.0–6.8.
- Sweet potatoes — matures in 90–120 days; tender; soil pH 5.5–6.5.
What to transplant in May
Harden seedlings off for a week before planting out, and water them in well.
- Sweet potatoes — matures in 90–120 days; tender; soil pH 5.5–6.5.
- Okra — matures in 50–65 days; tender; soil pH 6.0–6.8.
- Bell peppers — matures in 60–90 days; tender; soil pH 6.0–6.8.
What to harvest in May
Pick little and often: regular picking keeps beans, squash and cucumbers producing.
- Peas — hardy, matures in 60–70 days.
- Lettuce — hardy, matures in 45–60 days.
- Carrots — hardy, matures in 60–80 days.
- Beets — hardy, matures in 50–70 days.
- Potatoes — frost-tolerant, matures in 70–120 days.
- Broccoli — frost-tolerant, matures in 60–85 days.
- Onions — hardy, matures in 90–120 days.
May planting at a glance
| Crop | What to do | Days to maturity | Cold tolerance | Spacing |
|---|---|---|---|---|
| Broccoli | Start indoors | 60–85 | frost-tolerant | 18–24 in |
| Cabbage | Start indoors | 60–90 | frost-tolerant | 12–24 in |
| Kale | Start indoors | 50–65 | hardy | 12–18 in |
| Cauliflower | Start indoors | 55–80 | frost-tolerant | 18–24 in |
| Green beans | Direct sow | 50–65 | tender | 4–6 in |
All figures are broad published ranges from standard horticultural references, and they vary by variety, soil and weather. Check your local extension service for advice on your own garden.
Soil, water and feeding in May
May soil is warm and alive, so feed it rather than digging it. Side-dress tomatoes and peppers with compost, mulch beds thickly to hold moisture, and water at the base of plants in the morning. In dry spells, water deeply once or twice a week rather than sprinkling daily.
Frost and weather protection
Frost is normally finished by May in Zone 8: the average last spring frost is Mar 1–15, but do not take it for granted in an exposed garden. If a freak cold night is forecast, cover tender plants with fleece and water the soil during the day, since moist soil releases heat overnight. By mid-May the risk is usually past, and the bigger worry becomes heat and drought.
Pests and problems to watch
May is peak pest season: aphids, flea beetles, cucumber beetles and squash bugs all arrive now. Inspect leaves weekly, hand-pick beetles, and use row cover on young squash and cucumbers. Slugs love damp May nights, so protect young plants and keep mulch away from stems.
Frequently asked questions
What can I plant in May in Zone 8?
Almost everything warm-season: beans, corn, squash, cucumbers, okra, sweet potatoes, peppers, eggplant and basil. It is also the month to succession-sow lettuce, radishes and carrots.
When should I start fall crops in Zone 8?
Start fall brassicas like broccoli, cabbage and kale indoors in late May, so they are ready to transplant in June or July. Count back from your average first frost, Nov 15–Dec 1.
How do I keep May sowings from drying out?
Mulch beds, water in the morning, and sow small seeds a little deeper than usual. Shade cloth over lettuce keeps it from bolting in sudden heat.
What should I harvest in May in Zone 8?
Spring crops: peas, lettuce, spinach, carrots, beets, broccoli and early potatoes. Harvest lettuce before it bolts and peas while the pods are still sweet.
For the full year, browse the planting calendar hub. Nearby months: April in Zone 8, June in Zone 8, May in Zone 9. Use the garden planner to work out exact dates for your own garden.