San Jose, CA Frost Dates & Growing Season

The two dates every San Jose garden is planned around, plus ready-computed planting windows for the most popular crops.

Last spring frost
Jan 12
~50% chance of frost after
First fall frost
Dec 22
~50% chance of frost before
Growing season
344 days
frost-free stretch
USDA zone
≈ 10b
estimated from nearby reference
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Dec 20 Jan 12 Feb 14
First fall frost Jan 20 Dec 22 Dec 1
Hard freeze (28°F), median last Dec 31 · first Dec 28

Computed from NOAA 1991–2020 climate normals at the SAN JOSE station. "Safe" means frost past that date happens only about one year in ten. Your exact garden can still run days either way with elevation and terrain — check your own ZIP with the frost date lookup.

Planting windows for San Jose

Computed from San Jose's own frost dates. Click any crop for the full zone-10 growing guide — varieties, spacing, fall plantings, and more.

CropStart seeds indoorsTransplantDirect sow
🍅 Tomatoes Nov 17 – Dec 1 Jan 19 – Jan 26
🫑 Peppers Nov 3 – Nov 17 Jan 26 – Feb 2
🥬 Lettuce Dec 1 – Dec 15 Dec 15 – Dec 29 Dec 15 – Jan 12
🫛 Peas Dec 1 – Dec 15
🥕 Carrots Dec 22 – Jan 12
🥦 Broccoli Nov 24 – Dec 8 Dec 22 – Jan 5
🥬 Kale Dec 1 – Dec 15 Dec 15 – Dec 29 Dec 15 – Dec 29
🥒 Cucumbers Dec 15 – Dec 22 Jan 19 – Jan 26 Jan 19 – Jan 26
🥒 Zucchini Dec 15 – Dec 22 Jan 19 – Jan 26 Jan 19 – Jan 26
🫘 Green Beans (Bush) Jan 19 – Jan 26
🌽 Sweet Corn Jan 19 – Jan 26
🌿 Basil Dec 1 – Dec 15 Jan 19 – Jan 26 Jan 26 – Feb 2
🧄 Garlic Fall: Nov 10 – Dec 8

Want this for all 50 crops, or as a printable seed-shelf schedule? Use the planting calendar and the seed starting scheduler — both can use San Jose's dates automatically after a lookup.

Reading the season in San Jose

With roughly 344 frost-free days, San Jose gardens fit long-season crops — melons, winter squash, sweet potatoes — with room left for spring and fall rounds of greens and roots. The first frost around Dec 22 is late enough that fall planting is a full second season, not an afterthought.

Frequently asked questions

When is the last frost in San Jose, CA?

The average last spring frost in San Jose is around Jan 12, based on 1991–2020 climate normals. That's a median — about half of years see a later frost, so tender crops are safest going out a week or two after this date.

When is the first frost in San Jose, CA?

The average first fall frost in San Jose arrives around Dec 22. Crops still in the garden need to mature before then, and frost-tender plants need harvesting or protection as the date approaches.

How long is the growing season in San Jose?

About 344 frost-free days on average, from Jan 12 to Dec 22. That comfortably fits long-season crops like melons and winter squash, plus spring and fall plantings of cool-season vegetables.

What USDA zone is San Jose in?

USDA zone 10b on the 2023 Plant Hardiness Zone Map. Note that zones describe winter cold, not frost timing — these frost dates are the numbers to plan plantings around.