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USDA Hardiness Zone 9a

Frost Dates for 93640 — Mendota, California

Averages from Madera Muni Ap, Ca US, the nearest reporting station, 26.4 miles away.

Plant tender crops after February 12, and expect the first autumn freeze around November 30. That leaves about 293 frost-free days.

Last spring frost
February 12

50% probability

First fall frost
November 30

50% probability

Growing season
293 days

frost-free

Hardiness zone
9a

20 to 25°F annual low

Planting calendar for 93640

What to do and when, based on the frost normals for Mendota, California
WhenWhat to do
December 4 – December 18

Start peppers and aubergines indoors

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

December 18 – January 1

Start tomatoes indoors

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

January 15 – January 29

Sow peas, spinach, lettuce, radish outdoors

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

February 12 onward

Transplant tomatoes, peppers, basil, squash, cucumbers

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

by September 7

Sow the autumn crop of carrots, beets and brassicas

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

by November 16

Harvest tender crops, or be ready to cover them

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

November 30 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 February 12 to put tender plants — tomatoes, peppers, basil, squash — in the ground. That is the date by which half of years in Mendota, California are past their last freeze. Harvest before November 30, which leaves roughly 293 frost-free days.

ZIP 93640 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 California