Painted Rock Dam, AZ Frost Dates & Growing Season

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

Last spring frost
Jan 21
~50% chance of frost after
First fall frost
Dec 15
~50% chance of frost before
Growing season
328 days
frost-free stretch
USDA zone
≈ 9b
estimated from nearby reference
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Dec 24 Jan 21 Feb 18
First fall frost Jan 4 Dec 15 Nov 27
Hard freeze (28°F), median last Jan 8 · first Dec 28

Computed from NOAA 1991–2020 climate normals at the PAINTED ROCK DAM 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 Painted Rock Dam

Computed from Painted Rock Dam'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 Nov 26 – Dec 10 Jan 28 – Feb 4
🫑 Peppers Nov 12 – Nov 26 Feb 4 – Feb 11
🥬 Lettuce Dec 10 – Dec 24 Dec 24 – Jan 7 Dec 24 – Jan 21
🫛 Peas Dec 10 – Dec 24
🥕 Carrots Dec 31 – Jan 21
🥦 Broccoli Dec 3 – Dec 17 Dec 31 – Jan 14
🥬 Kale Dec 10 – Dec 24 Dec 24 – Jan 7 Dec 24 – Jan 7
🥒 Cucumbers Dec 24 – Dec 31 Jan 28 – Feb 4 Jan 28 – Feb 4
🥒 Zucchini Dec 24 – Dec 31 Jan 28 – Feb 4 Jan 28 – Feb 4
🫘 Green Beans (Bush) Jan 28 – Feb 4
🌽 Sweet Corn Jan 28 – Feb 4
🌿 Basil Dec 10 – Dec 24 Jan 28 – Feb 4 Feb 4 – Feb 11
🧄 Garlic Fall: Nov 3 – Dec 1

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 Painted Rock Dam's dates automatically after a lookup.

Reading the season in Painted Rock Dam

With roughly 328 frost-free days, Painted Rock Dam 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 15 is late enough that fall planting is a full second season, not an afterthought.

Frequently asked questions

When is the last frost in Painted Rock Dam, AZ?

The average last spring frost in Painted Rock Dam is around Jan 21, 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 Painted Rock Dam, AZ?

The average first fall frost in Painted Rock Dam arrives around Dec 15. 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 Painted Rock Dam?

About 328 frost-free days on average, from Jan 21 to Dec 15. That comfortably fits long-season crops like melons and winter squash, plus spring and fall plantings of cool-season vegetables.

What USDA zone is Painted Rock Dam 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.