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When to Plant Broccoli in Greenlee County, AZ

Broccoli is a nutrient-dense cool-season crop that produces large central heads followed by smaller side shoots. It is one of the most popular garden vegetables.

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 Broccoli may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Broccoli will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Broccoli 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 (70 days to spare)
Start indoors: Mar 6 Transplant: Apr 10 🍅 Harvest: Jun 12 – Jul 24
Recommended (50%) ✓ Fits season (78 days to spare)
Start indoors: Mar 18 Transplant: Apr 22 🍅 Harvest: Jun 24 – Aug 5
Safe Start (90%) ✓ Fits season (48 days to spare)
Start indoors: May 14 Transplant: Jun 18 🍅 Harvest: Aug 20 – Oct 1

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 Broccoli's growing requirements.

Soil pH

Your soil pH (7.1โ€“8.3) is more alkaline than Broccoli 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. Broccoli will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Broccoli.

Organic Matter

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

How to Plant Broccoli

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Broccoli

3
successive plantings in your 183-day season

Sow every 6.9 weeks. Last sowing by Jul 24 to harvest before frost.

For a dedicated fall crop, sow by Aug 13.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.3″/week
You supply
1.2″/week
Watering frequency 2-3 times/week
Season total 1,895 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Broccoli

Broccoli needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Broccoli 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 4.3" 0.5" 3.8" ๐Ÿšฟ Regular watering
May 4.3" 0.4" 3.9" ๐Ÿšฟ Regular watering
Jun 4.3" 0.5" 3.8" ๐Ÿšฟ Regular watering
Jul 4.3" 2.7" 1.6" ๐Ÿ’ง Light watering
Aug 4.3" 2.9" 1.4" ๐Ÿ’ง Light watering
Sep 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
Oct 4.3" 1.3" 3" 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.

Broccoli 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.

Broccoli needs ~1,594 GDD — county provides 3,888 GDD Excellent fit

Broccoli Planting Timeline โ€” Greenlee County, AZ

Broccoli Planting Calendar

Activity When Date Range
Start Indoors March 18 Mar 18 โ€“ Apr 1
Transplant Outdoors April 22 Apr 22 โ€“ May 6
Direct Sow April 8 Apr 8 โ€“ Apr 29
Harvest June 24 Jun 24 โ€“ Aug 5
Fall Sowing August 13 Aug 13 โ€“ Aug 27

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

60โ€“90 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 Broccoli in Greenlee County

Direct sow Broccoli 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 Broccoli with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Summer highs in Greenlee County reach 95ยฐF โ€” grow Broccoli as a spring or fall crop. Use shade cloth if planting in summer.

Common pests for Broccoli in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

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

General growing tips

Start seeds indoors 6-8 weeks before last frost. Provide consistent moisture to prevent hollow stems. Harvest heads before yellow flowers appear.

Recommended Broccoli Varieties for Greenlee County

Heat-tolerant broccoli โ€” plant as early spring or fall crop

Arcadia Marathon Green Magic

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Strawberries

Check more plant combinations with our Companion Planting Checker →

๐ŸŒพ Save Your Own Broccoli Seeds
Life Cycle Biennial
Pollination Cross-Pollinated (insects)
How to Collect Allow plants to flower 2nd year; collect dry pods.
Storage Store airtight; viable 5 years at 35ยฐF, under 50% humidity.

Isolate 1/2 mile from other brassicas. Biennial โ€” must overwinter roots.

Frequently Asked Questions

When should I plant Broccoli in Greenlee County, AZ?

Greenlee County is in Zone 7a with an average last frost of April 22. Plan your Broccoli 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.

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 Greenlee County, AZ. Local conditions may vary. Last updated: April 2026.