Sierra Vista, AZ Frost Dates & Growing Season

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

Last spring frost
Apr 5
~50% chance of frost after
First fall frost
Nov 9
~50% chance of frost before
Growing season
218 days
frost-free stretch
USDA zone
≈ 8a
estimated from nearby reference
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Mar 15 Apr 5 Apr 21
First fall frost Nov 23 Nov 9 Oct 23
Hard freeze (28°F), median last Mar 15 · first Nov 21

Computed from NOAA 1991–2020 climate normals at the SIERRA VISTA 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 Sierra Vista

Computed from Sierra Vista's own frost dates. Click any crop for the full zone-8 growing guide — varieties, spacing, fall plantings, and more.

CropStart seeds indoorsTransplantDirect sow
🍅 Tomatoes Feb 8 – Feb 22 Apr 12 – Apr 19
🫑 Peppers Jan 25 – Feb 8 Apr 19 – Apr 26
🥬 Lettuce Feb 22 – Mar 8 Mar 8 – Mar 22 Mar 8 – Apr 5
🫛 Peas Feb 22 – Mar 8
🥕 Carrots Mar 15 – Apr 5
🥦 Broccoli Feb 15 – Mar 1 Mar 15 – Mar 29
🥬 Kale Feb 22 – Mar 8 Mar 8 – Mar 22 Mar 8 – Mar 22
🥒 Cucumbers Mar 8 – Mar 15 Apr 12 – Apr 19 Apr 12 – Apr 19
🥒 Zucchini Mar 8 – Mar 15 Apr 12 – Apr 19 Apr 12 – Apr 19
🫘 Green Beans (Bush) Apr 12 – Apr 19
🌽 Sweet Corn Apr 12 – Apr 19
🌿 Basil Feb 22 – Mar 8 Apr 12 – Apr 19 Apr 19 – Apr 26
🧄 Garlic Fall: Sep 28 – Oct 26

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 Sierra Vista's dates automatically after a lookup.

Reading the season in Sierra Vista

With roughly 218 frost-free days, Sierra Vista 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 Nov 9 is late enough that fall planting is a full second season, not an afterthought.

Frequently asked questions

When is the last frost in Sierra Vista, AZ?

The average last spring frost in Sierra Vista is around Apr 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 Sierra Vista, AZ?

The average first fall frost in Sierra Vista arrives around Nov 9. 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 Sierra Vista?

About 218 frost-free days on average, from Apr 5 to Nov 9. That comfortably fits long-season crops like melons and winter squash, plus spring and fall plantings of cool-season vegetables.

What USDA zone is Sierra Vista in?

USDA zone 8a 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.