May garden tasks: Southeast
May in the Southeast marks the transition from spring productivity to heat-season management. In zone 8--9, daytime temperatures are regularly reaching 85--90°F by May, which ends production of cool-season crops and begins the heat stress window for tomatoes. In zone 7b, May is still productive.
May in the Southeast marks the transition from spring productivity to heat-season management. In zone 8—9, daytime temperatures are regularly reaching 85—90°F by May, which ends production of cool-season crops and begins the heat stress window for tomatoes. In zone 7b, May is still productive spring weather with warm-season crops hitting their stride.
Per Clemson HGIC, average high temperatures in May: Atlanta 79°F, Columbia SC 83°F, Charlotte 74°F. These temperatures are at or approaching the threshold where tomato blossom drop begins (night temps above 75°F and day temps above 95°F).
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Tomato and vegetable management
Per NC State Extension, May tomato care in the Southeast:
- Fertilize monthly with a balanced fertilizer or tomato-specific formula; do not over-apply nitrogen at this stage — excess N delays fruit ripening
- Manage irrigation: 1—2 inches per week via drip or soaker hose; overhead irrigation promotes fungal disease; water in the morning
- Stake or trellis: if not done at planting, do it now; indeterminate tomatoes grow rapidly in May
- Monitor for early blight and leaf spot: lower leaves showing concentric brown spots indicate early blight; per Clemson HGIC, remove affected leaves and apply copper fungicide preventively
What to pull and replant: Per Clemson HGIC, as cool-season crops finish in May, replace with heat-tolerant summer crops:
- Remove finished broccoli, spinach, lettuce
- Plant southern peas, okra, sweet potatoes, and edamame — all of which need warm soil (65°F+)
- Okra: direct sow May 1—15 in zones 8—9; wait until May 15—30 in zone 7b