USDA Zone 9a

Zone 9 · The Subtropical Edge

Average annual extreme minimum temperature: 20 to 25 °F (-6.7°C to -3.9°C).

Central Florida, the Gulf Coast, south Texas, and California's great valleys — 20 to 30°F winters where the calendar flips: the cool season becomes prime time and summer becomes the season to survive.

By the numbers

Median last frost: March 3
Median first frost: November 25
Median season: 268 days
ZIPs tracked: 1,767

Medians across every ZIP we track in zone 9a, derived from NOAA 1991–2020 climate normals. Look up your own ZIP for local dates — within a zone, frost varies by weeks.

Where you'll find zone 9

Central Florida (44% of Florida ZIPs in our data are 9a or 9b), the Gulf Coast from Houston and Beaumont through the Florida panhandle, Texas' coastal bend and Hill Country edge, coastal South Carolina's warmest corner around Charleston, and California's inland valleys and coastal belt.

Vegetables that earn their keep

Year-round with the right dates (UF): cool-season broccoli, cabbage, lettuce, spinach, peas, carrots, beets from fall through spring
Warm-season tomatoes, peppers, beans, squash, cucumbers in spring and again in fall
California's mild-winter pattern: fall/winter planting of cool-season crops rides the Nov–March rains (UC)

Fruits & perennials that overwinter

Citrus arrives: satsuma north of Orlando, Improved Meyer lemon (hardy into the low 20s), kumquat (~20°F); most citrus is hurt below 28°F for more than a few hours (UF, UC)
Low-chill peaches: UF's 'TropicBeauty', 'Flordaprince', 'Flordaglo' at ~100–150 chill hours
Pomegranate — only 200–300 chill hours needed (UC)
Low-chill apples (400–600 hours) in the cooler reaches (UC)

The flipped calendar

UF's vegetable guide says it directly: vegetables grow year-round in Florida if you respect the planting dates. The deep pattern of zone 9 is inversion — fall-through-spring is the productive season for everything leafy and cool-loving, while high summer is when seasoned gardeners rest beds, solarize soil, and start seedlings indoors for the fall garden (UF South Florida calendar's logic reaches up into 9).

Chill hours become the fruit gardener's arithmetic

Winter is now mild enough that insufficient cold limits temperate fruit. UC's chill-hour framework: most apples want 500–1,000 hours between 32–45°F; low-chill varieties get by on 400–600; pomegranates need only 200–300. UF's low-chill peach program (100–150 hours for the warmest varieties) exists precisely for this band. Match the variety's chill requirement to your local accumulation — and note that warming winters are shrinking it (UC).

Citrus, with a thermometer

Most citrus suffers real damage below 28°F held more than a few hours (UC). In zone 9 that's a few nights a winter: the difference between losing and keeping a tree is often just watering ahead of a freeze and covering young trees when forecasts approach 30°F (UF, UC).

The summer gauntlet

Tomato blossom drop above 70°F nights (UGA), disease pressure that mild winters never reset, nematodes in sandy soils, and — along the Gulf and Atlantic — hurricane season. Zone 9 asks less "will it freeze?" than "will it cook, rot, or blow over?" The answers: plant the heat-tender crops early and again in fall, choose resistant varieties, and treat August the way Minnesotans treat January.

Plant guides, timed to your frost dates

Every guide gives its planting calendar relative to your last frost — the dates above (or your ZIP's) drop straight in.