Houston, TX

Houston's 300-day frost-free season running from February 13 to December 9 offers gardeners one of the longest planting windows in the country. However, the season's length masks its true constraint: heat, not cold. Winter temperatures rarely drop below 25°F, so tender perennials like figs, pomegranates, and Asian persimmons thrive where they struggle in cooler zones. The real limitation is the reverse: a hard freeze after February, combined with the arrival of sustained 90°F+ temperatures by May, compresses the optimal window for cool-season crops to just six or seven weeks (late January through early March). Summer heat is the dominant gardening force in Houston. Heat-loving plants (figs, goji berries, sweet peppers, jujubes) flourish from May onward, but cool-season crops (lettuce, peas, brassicas) must be off the beds before June heat arrives. Soil temperatures remain warm enough for continuous germination from March through October, which is an advantage for succession planting of warm-season crops but complicates winter vegetable gardening. Humidity is persistent and creates fungal disease pressure throughout the year, especially in the growing season. The combination of long heat and high humidity means crop selection and timing matter more than in zones with a traditional spring-to-fall cycle.

Late spring freezes remain a genuine risk through early March, even though the last frost date is February 13. Many tender perennials (fig buds, newly grafted trees, passion fruit vines) survive the winter but break dormancy in February's mild weather, then get hit by a 25°F night in early March. Cool-season crops fail not from cold but from the reverse problem: premature bolting when spring temperatures hit 85°F in late April before harvest.

Summer heat (May-September) stops most traditional vegetables dead. Tomato fruit sets poorly above 95°F; peppers slow down at similar temperatures. Humidity combines with heat to encourage powdery mildew, southern blight, and root rot across the bed. Drainage becomes critical because Houston's clay soils and frequent summer thunderstorms create waterlogging. The third challenge is compressed timing: to grow cool-season crops at all, they must be seeded or transplanted by late January and off the beds by early April, a race many gardeners lose to unseasonably warm March weeks.

Use the early-season window strategically. Seed brassicas, lettuce, and peas in mid-January (6 weeks before the last frost) so they mature before May heat arrives. Plan to harvest and remove these beds by late April. Then immediately succession-plant warm-season peppers and okra in their place, taking advantage of warm soil and reliable sunshine.

Plant tomatoes on the early side, then again in midsummer. Seed indoors in late December or buy transplants in late January, planting outside in early February when frost risk is low but before heat sets in. This spring crop finishes by July. Then, in late July, seed a second crop for a fall harvest that rides cooler October and November weather.

Choose varieties bred for heat and humidity. Figs, pomegranates, jujubes, and Asian persimmons are thermally suited to Houston. For annual vegetables, seek varieties noted as heat-tolerant: tomato ('Heatwave', 'Phoenix'); pepper ('Jalapeño', 'Thai Hot'); and okra (almost any variety tolerates heat well). Avoid varieties bred for cool climates.