Heat Mode: Surviving a Texas Summer

Why it matters

Texas summer heat stops tomatoes from setting fruit and cooks unprotected beds. Gardeners who switch to heat-loving crops, mulch heavily and use light shade keep producing all summer. The same gardeners are ready for the fall restart, which is often Texas's best season.

Step by step

1. Mulch 4 inches deep Put down enough organic mulch to settle at 4 inches. That's about 8 inches of loose straw. Light-colored mulches like compost keep soil cooler in summer.
2. Hang light shade cloth For vegetables, extension sources point to light shade cloth of about 20-40%, with 30% the most common choice. AgriLife research says shade cloth under 50% works best for general gardening.
3. Water early and more often AgriLife's vegetable specialist suggests running drip about an hour in the morning and an hour in the afternoon daily during peak summer, then adjusting for your soil. Check soil first, since overwatering rots roots.
4. Plant heat lovers in June Okra, southern peas, cantaloupe, Malabar spinach and sweet potatoes thrive in Texas heat. Plant sweet potato slips by the end of June for a fall harvest.
5. Expect tomatoes to pause When days run in the 90s and nights stay warm, most tomatoes stop setting new fruit, though fruit already on the vine keeps ripening. For summer fruit, plant heat-set varieties like Heatwave, Sunmaster, Solar Fire or Solar Set from mid-June to early July.
6. Pull worn-out spring crops Clear spent spring plants and weeds. Don't compost them if they had insects or disease.
7. Solarize empty beds in July Wet the soil and cover it tightly with clear plastic for at least a month to cut nematodes. Black plastic won't get hot enough.
8. Restart for fall Set fall tomato transplants about 100 days before your first frost, and use short-season varieties in North Texas. Shade new transplants after 3 p.m. and water them daily for about 2 weeks.

Key facts

• Mulch: 4 inches settled, which means about 8 inches of straw at first. Well-mulched gardens can yield up to 50% more (AgriLife E-512).
• Shade cloth for vegetables: 20-40%, with about 30% most common (Univ. of Delaware). AgriLife research says shade under 50% is most effective for general gardening (Bexar County Master Gardeners citing Texas A&M).
• Tomato fruit set: Oklahoma State says set suffers when days stay above about 92°F or nights fall outside 60-70°F.
• Auburn (ANR-2717) says flowers often drop above 85°F days or 72°F nights, and heat lasting a week or less usually does little harm.
• AgriLife's Masabni says fruit set on most tomatoes stops when highs reach the 90s and nights stay in the 80s.
• Water needs rise from about 1/2 inch a week in May to 1 inch or more in July (AgriLife).
• Snap beans drop blossoms above about 85-90°F (AgriLife, Masabni).
• Solarize for at least 1 month in July under clear plastic (AgriLife).
• Fall tomatoes go in about 100 days before the average first frost. In Dallas, that means the first half of August (Dallas County Master Gardeners, citing AgriLife).
• Vegetables need at least 8 hours of direct sun. For young fall transplants, afternoon shade after 3 p.m. helps (AgriLife fall guide).

Texas notes

• AgriLife's last good dates for fall tomatoes, peppers and eggplant: Jul 25 in Region III (Central Texas) and Sep 1 in Region V (Rio Grande Valley).
• A late-August or early-September tomato planting can produce until the first freeze. In North Texas and the Panhandle, use varieties that mature in about 45 days (AgriLife Today).
• AgriLife suggests planting tomatoes 3-4 times a year, about 5-6 weeks apart, to avoid a summer gap.
• Okra produces into fall. Pick pods every 1-2 days while young, or they turn tough (Williamson County AgriLife).
• Winds as low as 15 mph slow growth and cut yields, so windbreaks help in West Texas (AgriLife).
• Fall transplants in small pots need daily water for about 2 weeks until roots settle (AgriLife).