Casa Grande, AZ Frost Dates & Growing Season

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

Last spring frost
Feb 5
~50% chance of frost after
First fall frost
Dec 6
~50% chance of frost before
Growing season
304 days
frost-free stretch
USDA zone
≈ 9b
estimated from nearby reference
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Jan 5 Feb 5 Feb 28
First fall frost Dec 29 Dec 6 Nov 18
Hard freeze (28°F), median last Jan 14 · first Dec 22

Computed from NOAA 1991–2020 climate normals at the CASA GRANDE 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 Casa Grande

Computed from Casa Grande's own frost dates. Click any crop for the full zone-9 growing guide — varieties, spacing, fall plantings, and more.

CropStart seeds indoorsTransplantDirect sow
🍅 Tomatoes Dec 11 – Dec 25 Feb 12 – Feb 19
🫑 Peppers Nov 27 – Dec 11 Feb 19 – Feb 26
🥬 Lettuce Dec 25 – Jan 8 Jan 8 – Jan 22 Jan 8 – Feb 5
🫛 Peas Dec 25 – Jan 8
🥕 Carrots Jan 15 – Feb 5
🥦 Broccoli Dec 18 – Jan 1 Jan 15 – Jan 29
🥬 Kale Dec 25 – Jan 8 Jan 8 – Jan 22 Jan 8 – Jan 22
🥒 Cucumbers Jan 8 – Jan 15 Feb 12 – Feb 19 Feb 12 – Feb 19
🥒 Zucchini Jan 8 – Jan 15 Feb 12 – Feb 19 Feb 12 – Feb 19
🫘 Green Beans (Bush) Feb 12 – Feb 19
🌽 Sweet Corn Feb 12 – Feb 19
🌿 Basil Dec 25 – Jan 8 Feb 12 – Feb 19 Feb 19 – Feb 26
🧄 Garlic Fall: Oct 25 – Nov 22

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 Casa Grande's dates automatically after a lookup.

Reading the season in Casa Grande

With roughly 304 frost-free days, Casa Grande 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 6 is late enough that fall planting is a full second season, not an afterthought.

Frequently asked questions

When is the last frost in Casa Grande, AZ?

The average last spring frost in Casa Grande is around Feb 5, 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 Casa Grande, AZ?

The average first fall frost in Casa Grande arrives around Dec 6. 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 Casa Grande?

About 304 frost-free days on average, from Feb 5 to Dec 6. That comfortably fits long-season crops like melons and winter squash, plus spring and fall plantings of cool-season vegetables.

What USDA zone is Casa Grande in?

USDA zone 9b 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.