Blog

When to Plant Zucchini in Union County, NM

Zucchini is an incredibly prolific summer squash that can produce an abundance of fruit from just a few plants. It is versatile in the kitchen from grilling to baking.

Union County, New Mexico is in USDA Zone 5b. The average last spring frost is April 30 and the first fall frost is October 9, giving you a growing season of approximately 162 days.

At an elevation of 6,384 feet, Union County receives approximately 17.5 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 85ยฐF, providing good warmth for Zucchini during the growing season. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Zucchini will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Zucchini successfully. Mulch heavily to conserve soil moisture.

Union County, NM (Zone 5b) Moderate season
162 days
Last Spring Frost April 30
162 growing days
First Fall Frost October 9

Union County Soil Profile

Soil Type

Sandy Loam

Soil pH

6.9-8.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (44 days to spare)
Start indoors: Mar 21 Transplant: May 9 🍅 Harvest: Jun 27 – Aug 22
Recommended (50%) ✓ Fits season (43 days to spare)
Start indoors: Mar 26 Transplant: May 14 🍅 Harvest: Jul 2 – Aug 27
Safe Start (90%) ✓ Fits season (41 days to spare)
Start indoors: Apr 12 Transplant: May 31 🍅 Harvest: Jul 19 – Sep 13

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.5″/week
You supply
1.0″/week
Watering frequency 2-3 times/week
Season total 1,464 gal / 100 sq ft
Drought risk

Water stress score is 10/10 โ€” consider drought-tolerant varieties and mulching

Zucchini needs ~722 GDD — county provides 2,227 GDD Excellent fit

Zucchini Planting Timeline โ€” Union County, NM

Zucchini Planting Calendar

Activity When Date Range
Start Indoors March 26 Mar 26 โ€“ Apr 9
Transplant Outdoors May 14 May 14 โ€“ May 28
Direct Sow May 7 May 7 โ€“ May 28
Harvest July 2 Jul 2 โ€“ Aug 27

Plant 1" deep ยท 30" apart ยท Rows 42" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
April Start Indoors
May Transplant Outdoors Direct Sow
June โ€”
July Harvest
August Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

45โ€“60 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 5b

Growing Season

162 days

Growing Tips for Union County

Direct sow after last frost. Harvest when fruits are 6-8 inches long for best flavor and texture. Check plants daily in summer as fruits can double in size overnight.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Level Up Your Garden

Frequently Asked Questions

When should I plant Zucchini in Union County, NM?

Union County is in Zone 5b with an average last frost of April 30. Plan your Zucchini planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Union County, NM?

Union County, New Mexico is in USDA Hardiness Zone 5b. The average last spring frost is April 30 and first fall frost is October 9.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Union County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Union County, NM. Local conditions may vary. Last updated: April 2026.