May marks the shift into early summer conditions in the warm-winter zones, and gardens respond fast with rapid growth. Warm-season crops should be planted and growing strongly now, and succession sowing keeps harvests coming even as temperatures climb. Stay ahead of heat stress by mulching, watering consistently, and planting in the coolest part of the day — and in the hottest areas, begin planning for shade cloth and other summer protection.
Indoors (fresh harvests):
- Microgreens: peas, broccoli, sunflowers, arugula
- Sprouts: alfalfa, broccoli, radish, mung
- Herbs & greens under lights: chives, parsley, mint
Transplants to move outdoors: Most warm-season crops should already be in the ground. If you have heat-tolerant starts on hand, get them out early in the month before conditions get too stressful.
Crops that can be directly sown outdoors in May: okra, sweet potato slips, cowpeas, yard-long beans, Malabar spinach, Armenian cucumber, and other heat-tolerant varieties. Standard cucumbers, squash, and beans can still go in early May in many areas.
Cover crops: cowpeas, sunn hemp, buckwheat, sorghum-sudangrass
Note: Cool-season crops are wrapping up. The focus shifts to heat-tolerant varieties and keeping the soil covered.
Tip: A Southern California zone 10 can be very different from a Florida zone 10. Consider checking with your state Extension Service office for more specific recommendations and guidelines.
Use your USDA zone as a guide. Microclimates matter — coastal/urban spots run warmer; high elevation runs colder.
