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USDA Hardiness Zone 9a

Frost Dates for 36575 — Semmes, Alabama

Averages from Mobile, Al US, the nearest reporting station, 6.2 miles away.

Plant tender crops after March 3, and expect the first autumn freeze around November 25. That leaves about 268 frost-free days.

Last spring frost
March 3

50% probability

First fall frost
November 25

50% probability

Growing season
268 days

frost-free

Hardiness zone
9a

20 to 25°F annual low

Planting calendar for 36575

What to do and when, based on the frost normals for Semmes, Alabama
WhenWhat to do
December 23 – January 6

Start peppers and aubergines indoors

They need eight to ten weeks under lights before they can go out.

January 6 – January 20

Start tomatoes indoors

Six to eight weeks gives a transplant big enough to set fruit early.

February 3 – February 17

Sow peas, spinach, lettuce, radish outdoors

These tolerate light frost and prefer to germinate in cool soil.

March 3 onward

Transplant tomatoes, peppers, basil, squash, cucumbers

The average last freeze has passed — still watch the actual forecast.

by September 2

Sow the autumn crop of carrots, beets and brassicas

They need about twelve weeks to size up before growth stops.

by November 11

Harvest tender crops, or be ready to cover them

A first freeze two weeks early is well within normal variation.

November 25 onward

Plant garlic, mulch beds, lift tender bulbs

Garlic wants a cold spell; bare soil loses structure over winter.

What these dates mean

Wait until after March 3 to put tender plants — tomatoes, peppers, basil, squash — in the ground. That is the date by which half of years in Semmes, Alabama are past their last freeze. Harvest before November 25, which leaves roughly 268 frost-free days.

ZIP 36575 sits in USDA hardiness zone 9a, meaning the average coldest night of the year falls between 20 to 25°F. Zone decides what survives the winter; frost dates decide when to plant each spring. They are different questions, and a plant can pass one and fail the other.

These are thirty-year NOAA averages for 1991–2020, not a forecast. Any individual year can frost two to three weeks either side of these dates, so check the actual forecast before planting out.

Other zone 9a ZIP codes in Alabama