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When to Plant Peas in Maricopa County, AZ

Maricopa County, Arizona Zone 9b May

This month in Maricopa County, Arizona

May is a pivotal month for Maricopa County, Arizona gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost January 31
Avg. first frost December 6
Soil temp (4") 66°F
Watering Critical
Pest pressure High
Daylight 13.7 hrs
  1. Pick peas

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

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Peas are a cool-season legume that fixes nitrogen in the soil. Garden peas are shelled, while snap and snow peas are eaten pod and all.

Maricopa County, Arizona is in USDA Zone 9b. The average last spring frost is January 31 and the first fall frost is December 6, giving you a growing season of approximately 309 days.

At an elevation of 4,014 feet, Maricopa County receives approximately 12.5 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 108°F, so Peas may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Peas will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Peas successfully. Mulch heavily to conserve soil moisture.

Maricopa County, AZ (Zone 9b) Year-round
309 days
Last Spring Frost January 31
309 growing days
First Fall Frost December 6

Maricopa County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.2-8.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (206 days to spare)
Start indoors: Dec 20 Transplant: Jan 17 🍅 Harvest: Mar 14 – May 9
Recommended (50%) ✓ Fits season (197 days to spare)
Start indoors: Jan 3 Transplant: Jan 31 🍅 Harvest: Mar 28 – May 23
Safe Start (90%) ✓ Fits season (192 days to spare)
Start indoors: Jan 30 Transplant: Feb 27 🍅 Harvest: Apr 24 – Jun 19

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 Maricopa County

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

Soil pH

Your soil pH (7.2–8.5) is more alkaline than Peas prefers (6.0–7.5). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is low (0.7%). Add 2-3 inches of compost before planting Peas.

How to Plant Peas

1"
Planting Depth
4"
Between Plants
18"
Between Rows

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Peas

6
successive plantings in your 309-day season

Sow every 6.3 weeks. Last sowing by Sep 27 to harvest before frost.

For a dedicated fall crop, sow by Oct 11.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.2″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 1,757 gal / 100 sq ft
Drought risk

Water stress score is 10/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Peas

Peas needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Peas Needs Rainfall You Supplement Action
Jan 3" 0.9" 2.1" 🚿 Regular watering
Feb 3" 0.8" 2.2" 🚿 Regular watering
Mar 3" 0.7" 2.3" 🚿 Regular watering
Apr 3" 0.5" 2.5" 🚿 Regular watering
May 3" 0.3" 2.7" 🚿 Regular watering
Jun 3" 0.4" 2.6" 🚿 Regular watering
Jul 3" 2.1" 0.9" 💧 Light watering
Aug 3" 2.3" 0.7" 💧 Light watering
Sep 3" 1.9" 1.1" 💧 Light watering
Oct 3" 1.2" 1.8" 🚿 Regular watering
Nov 3" 0.6" 2.4" 🚿 Regular watering
Dec 3" 0.8" 2.2" 🚿 Regular watering

Water needs are for active growing months only (Jan–Dec in Maricopa County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Peas 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" — every day above 50°F 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.

Peas needs ~1,938 GDD — county provides 9,610 GDD Excellent fit

Peas Planting Timeline — Maricopa County, AZ

Peas Planting Calendar

Activity When Date Range
Start Indoors January 3 Jan 3 – Jan 17
Transplant Outdoors January 31 Jan 31 – Feb 14
Direct Sow January 10 Jan 10 – Jan 31
Harvest March 28 Mar 28 – May 23
Fall Sowing October 11 Oct 11 – Oct 25

Plant 1" deep · 4" apart · Rows 18" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.7"/week · 1-2 times/week

📅 Days to Maturity

55–70 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 9b

📆 Growing Season

309 days in Maricopa County

Growing Tips for Peas in Maricopa County

Direct sow Peas outdoors after January 31 in Maricopa County when soil has warmed and frost danger has passed.

Sandy soil in Maricopa County dries quickly — mulch Peas with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Summer highs in Maricopa County reach 108°F — grow Peas as a spring or fall crop. Use shade cloth if planting in summer.

Common pests for Peas in this region include bean beetles and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow as early as soil can be worked in spring. Inoculate seeds with rhizobium for best nitrogen fixation. Provide trellising for climbing varieties.

Recommended Peas Varieties for Maricopa County

Heat-tolerant peas — plant very early or as fall crop

Wando (68d) Oregon Sugar Pod (60d)

Companion Planting

Good Companions

Avoid Planting Near

  • Onion
  • Garlic

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Peas Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Let pods dry brown and papery on the vine.
Storage Store airtight; viable 3 years at 35°F, under 45% humidity.

Very easy to save. Self-pollinating means varieties stay true.

Frequently Asked Questions

When should I plant Peas in Maricopa County, AZ?

Maricopa County is in Zone 9b with an average last frost of January 31. Plan your Peas planting based on this frost date — see the calendar above for exact timing.

What planting zone is Maricopa County, AZ?

Maricopa County, Arizona is in USDA Hardiness Zone 9b. The average last spring frost is January 31 and first fall frost is December 6.

🌱

Your Maricopa County Garden Planner — Free

A 24-page printable planner built for Maricopa County (Zone 9b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Maricopa County, AZ. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.