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When to Plant Butternut Squash in Greenlee County, AZ

Butternut squash is a popular winter squash with a long neck, small seed cavity, and sweet, nutty orange flesh. It stores exceptionally well for months.

Greenlee County, Arizona is in USDA Zone 7a. The average last spring frost is April 22 and the first fall frost is October 22, giving you a growing season of approximately 183 days.

At an elevation of 4,156 feet, Greenlee County receives approximately 14.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 95ยฐF, so Butternut Squash may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Butternut Squash will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Butternut Squash successfully. Mulch heavily to conserve soil moisture.

Greenlee County, AZ (Zone 7a) Moderate season
183 days
Last Spring Frost April 22
183 growing days
First Fall Frost October 22

Greenlee County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.1-8.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (35 days to spare)
Start indoors: Mar 13 Transplant: Apr 24 🍅 Harvest: Jul 24 – Aug 28
Recommended (50%) ✓ Fits season (43 days to spare)
Start indoors: Mar 25 Transplant: May 6 🍅 Harvest: Aug 5 – Sep 9
Safe Start (90%) ✓ Fits season (13 days to spare)
Start indoors: May 21 Transplant: Jul 2 🍅 Harvest: Oct 1 – Nov 5

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.

Soil Compatibility in Greenlee County

How your county's soil matches Butternut Squash's growing requirements.

Soil pH

Your soil pH (7.1โ€“8.3) is more alkaline than Butternut Squash prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Greenlee County warms quickly in spring but drains fast. Butternut Squash will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Butternut Squash.

Organic Matter

Organic matter is low (0.9%). Add 2-3 inches of compost before planting Butternut Squash.

How to Plant Butternut Squash

1"
Planting Depth
30"
Between Plants
42"
Between Rows

Plant Water Budget

Plant needs
1.1″/week
Rainfall provides
0.3″/week
You supply
1.3″/week
Watering frequency 2-3 times/week
Season total 2,149 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Butternut Squash

Butternut Squash needs approximately 1.1 inches of water per week (4.8" per month). Here's how your county's rainfall compares month by month.

Month Butternut Squash Needs Rainfall You Supplement Action
Jan โ€” 1" 0" โ„๏ธ Dormant
Feb โ€” 0.8" 0" โ„๏ธ Dormant
Mar โ€” 0.8" 0" โ„๏ธ Dormant
Apr 4.8" 0.5" 4.3" ๐Ÿšฟ Regular watering
May 4.8" 0.4" 4.4" ๐Ÿšฟ Regular watering
Jun 4.8" 0.5" 4.3" ๐Ÿšฟ Regular watering
Jul 4.8" 2.7" 2.1" ๐Ÿ’ง Light watering
Aug 4.8" 2.9" 1.9" ๐Ÿ’ง Light watering
Sep 4.8" 1.7" 3.1" ๐Ÿšฟ Regular watering
Oct 4.8" 1.3" 3.5" ๐Ÿšฟ Regular watering
Nov โ€” 0.9" 0" โ„๏ธ Dormant
Dec โ€” 1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Greenlee County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Butternut Squash Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Butternut Squash needs ~2,072 GDD — county provides 3,888 GDD Excellent fit

Butternut Squash Planting Timeline โ€” Greenlee County, AZ

Butternut Squash Planting Calendar

Activity When Date Range
Start Indoors March 25 Mar 25 โ€“ Apr 8
Transplant Outdoors May 6 May 6 โ€“ May 20
Direct Sow April 29 Apr 29 โ€“ May 20
Harvest August 5 Aug 5 โ€“ Sep 9

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 Direct Sow
May Transplant Outdoors Direct Sow
June โ€”
July โ€”
August Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1.1"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

85โ€“110 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

183 days in Greenlee County

Growing Tips for Butternut Squash in Greenlee County

Direct sow Butternut Squash outdoors after April 22 in Greenlee County when soil has warmed and frost danger has passed.

Sandy soil in Greenlee County dries quickly โ€” mulch Butternut Squash with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Common pests for Butternut Squash in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.

Greenlee County receives only 14" of rain annually. Butternut Squash needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Start seeds indoors 3 weeks early or direct sow after frost. Allow 6-8 feet for sprawling vines. Harvest when the skin is hard and uniformly tan. Cure in the sun for 10 days.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Butternut Squash in Greenlee County, AZ?

Greenlee County is in Zone 7a with an average last frost of April 22. Plan your Butternut Squash planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Greenlee County, AZ?

Greenlee County, Arizona is in USDA Hardiness Zone 7a. The average last spring frost is April 22 and first fall frost is October 22.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Greenlee County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.

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