Zone 10a: What Grows and How to Garden There

What a zone 10a winter means

Zone 10a is where frost becomes the exception rather than the rule. In most of its ZIP codes a 32°F night happens in fewer than half of winters, so the garden is shaped by heat, rainfall and the occasional cold snap rather than by frost dates. Arizona Extension lists 10a among the zones where citrus grows safely. Tropical plants can still be hurt above freezing: UF/IFAS notes chilling injury below 50°F on tropical species, and young mango and avocado trees can die in a brief freeze.

Where zone 10a is

Zone 10a covers central Florida around Orlando, Palm Bay and Port St. Lucie; the Inland Empire and inland Orange and Los Angeles counties in California, including Riverside, San Bernardino, Ontario, Fontana, Anaheim and Santa Clarita; parts of Arizona’s low desert; and the Texas Gulf Coast from Galveston and Corpus Christi to the Rio Grande Valley around McAllen and Brownsville.

Fruit

• Citrus: all types, including lemons and limes, though the most tender still need cover in a rare freeze.
• Avocado: match the type to your cold risk (see the FAQ). UF/IFAS warns that laurel wilt has killed many avocado trees in South Florida.
• Mango: possible, with protection for young trees.
• Papaya and banana: UF/IFAS says papaya thrives at 70-90°F and is damaged below 31°F; bananas regrow if frozen back.
• Low-chill fruit: see the FAQ. Chill varies a lot from year to year; UF/IFAS counted about 350 chill units near Orlando in one winter and about 80 in a warm one.

Perennials and bulbs

Tropical and subtropical bulbs that need no chilling, such as amaryllis, crinum, rain lilies, cannas and agapanthus, return every year (UF/IFAS). Tulips are grown only as annuals from pre-chilled bulbs.

Special concerns

• Season: in Florida, plant tomatoes in late winter or early spring, before nights average 80°F, and grow cool-season vegetables from fall into spring (UF/IFAS).
• Pests: root-knot nematodes thrive in warm, sandy soils; rotate crops and solarize in summer.
• Cold snaps: cover tender plants with fabric reaching the ground, water beforehand, and delay pruning freeze damage until new growth appears (UF/IFAS).