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When to Plant Peppers in Pima County, AZ

Sweet peppers are warm-season crops producing fruits in a rainbow of colors. They turn from green to red, yellow, or orange as they ripen, increasing in sweetness.

Pima County, Arizona is in USDA Zone 9a. The average last spring frost is April 1 and the first fall frost is November 9, giving you a growing season of approximately 222 days.

At an elevation of 4,327 feet, Pima County receives approximately 14.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 103ยฐF, so Peppers may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Peppers will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Peppers successfully. Mulch heavily to conserve soil moisture.

Pima County, AZ (Zone 9a) Long season
222 days
Last Spring Frost April 1
222 growing days
First Fall Frost November 9

Pima County Soil Profile

Soil Type

Sandy Loam

Soil pH

6.8-8.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (85 days to spare)
Start indoors: Feb 8 Transplant: Mar 29 🍅 Harvest: May 31 – Aug 9
Recommended (50%) ✓ Fits season (82 days to spare)
Start indoors: Feb 18 Transplant: Apr 8 🍅 Harvest: Jun 10 – Aug 19
Safe Start (90%) ✓ Fits season (75 days to spare)
Start indoors: Mar 24 Transplant: May 12 🍅 Harvest: Jul 14 – Sep 22

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 Pima County

How your county's soil matches Peppers's growing requirements.

Soil pH

Your soil pH (6.8โ€“8.3) is more alkaline than Peppers prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Drainage

Drainage is adequate for Peppers.

Organic Matter

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

How to Plant Peppers

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

Succession Planting Peppers

4
successive plantings in your 222-day season

Sow every 6.9 weeks. Last sowing by Aug 11 to harvest before frost.

Plant Water Budget

Plant needs
1.1″/week
Rainfall provides
0.3″/week
You supply
1.4″/week
Watering frequency 2-3 times/week
Season total 2,745 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Peppers

Peppers 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 Peppers Needs Rainfall You Supplement Action
Jan โ€” 0.9" 0" โ„๏ธ Dormant
Feb โ€” 0.8" 0" โ„๏ธ Dormant
Mar โ€” 0.7" 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" 3.2" 1.6" ๐Ÿ’ง Light watering
Sep 4.8" 1.9" 2.9" ๐Ÿšฟ Regular watering
Oct 4.8" 1.4" 3.4" ๐Ÿšฟ Regular watering
Nov 4.8" 0.7" 4.1" ๐Ÿšฟ Regular watering
Dec โ€” 0.9" 0" โ„๏ธ Dormant

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

Peppers 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.

Peppers needs ~2,044 GDD — county provides 6,049 GDD Excellent fit

Peppers Planting Timeline โ€” Pima County, AZ

Peppers Planting Calendar

Activity When Date Range
Start Indoors February 18 Feb 18 โ€“ Mar 4
Transplant Outdoors April 8 Apr 8 โ€“ Apr 22
Direct Sow April 1 Apr 1 โ€“ Apr 22
Harvest June 10 Jun 10 โ€“ Aug 19

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

Month-by-Month Timeline

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

60โ€“90 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 9a

๐Ÿ“† Growing Season

222 days in Pima County

Growing Tips for Peppers in Pima County

Direct sow Peppers outdoors after April 01 in Pima County when soil has warmed and frost danger has passed.

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

With summer highs reaching 103ยฐF in Pima County, provide afternoon shade for Peppers and water deeply in the morning.

Common pests for Peppers in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.

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

General growing tips

Start seeds indoors 8-10 weeks before last frost. Transplant when nighttime temperatures stay above 55F. Avoid high-nitrogen fertilizers which promote leaves over fruit.

Recommended Peppers Varieties for Pima County

Heat-loving peppers that thrive in your hot summers

NuMex Joe E. Parker Ancho 211 Mariachi

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel
  • Kohlrabi

Check more plant combinations with our Companion Planting Checker →

๐ŸŒพ Save Your Own Peppers Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Remove seeds from fully ripe (red/orange) fruit.
Storage Store airtight; viable 4 years at 35ยฐF, under 50% humidity.

Isolate 300 ft for purity. Hot and sweet peppers can cross-pollinate.

Frequently Asked Questions

When should I plant Peppers in Pima County, AZ?

Pima County is in Zone 9a with an average last frost of April 1. Plan your Peppers planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Pima County, AZ?

Pima County, Arizona is in USDA Hardiness Zone 9a. The average last spring frost is April 1 and first fall frost is November 9.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Pima County gardeners in Zone 9a 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 Pima County, AZ. Local conditions may vary. Last updated: April 2026.