When to Plant Potatoes in Coconino County, AZ
Coconino County, Arizona gardeners: here's your May plan
A quick May briefing for Coconino County, Arizona gardeners — what's urgent, what's next, and what can wait.
June prep starts now
- Transplants going out: potatoes
- Direct-sowing: potatoes
Potatoes are a versatile staple crop that produces tubers underground. They come in hundreds of varieties with varying colors, textures, and maturity dates.
Coconino County, Arizona is in USDA Zone 7a. The average last spring frost is May 28 and the first fall frost is September 27, giving you a growing season of approximately 122 days.
At an elevation of 7,869 feet, Coconino County receives approximately 13.9 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 96°F, so Potatoes may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Potatoes will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Potatoes successfully. Mulch heavily to conserve soil moisture.
Coconino County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.2-8.6
Drainage
Well Drained
Plant Planting Risk Windows
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 Coconino County
How your county's soil matches Potatoes's growing requirements.
Soil pH
Your soil pH (7.2–8.6) is more alkaline than Potatoes prefers (5.0–6.5). Add sulfur or peat moss to lower pH.
Soil Texture
Sandy soil in Coconino County warms quickly in spring but drains fast. Potatoes will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Potatoes.
Organic Matter
Organic matter is low (0.8%). Add 2-3 inches of compost before planting Potatoes.
How to Plant Potatoes
How Much Potatoes to Grow
For a family of 4, plant approximately 20 potatoes plants in about 50 sq ft. In Coconino County's 122-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Plant Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Potatoes
Potatoes needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Potatoes Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1" | 0" | ❄️ Dormant |
| Feb | — | 0.7" | 0" | ❄️ Dormant |
| Mar | — | 0.8" | 0" | ❄️ Dormant |
| Apr | — | 0.4" | 0" | ❄️ Dormant |
| May | 4.3" | 0.3" | 4" | 🚿 Regular watering |
| Jun | 4.3" | 0.4" | 3.9" | 🚿 Regular watering |
| Jul | 4.3" | 2.6" | 1.7" | 💧 Light watering |
| Aug | 4.3" | 3" | 1.3" | 💧 Light watering |
| Sep | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Oct | — | 1.3" | 0" | ❄️ Dormant |
| Nov | — | 0.8" | 0" | ❄️ Dormant |
| Dec | — | 0.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Coconino County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Potatoes 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.
Potatoes Planting Timeline — Coconino County, AZ
Potatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 9 | Apr 9 – Apr 23 |
| Transplant Outdoors | June 11 | Jun 11 – Jun 25 |
| Direct Sow | June 4 | Jun 4 – Jun 25 |
| Harvest | August 20 | Aug 20 – Oct 29 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | — |
| June | Transplant Outdoors Direct Sow |
| July | — |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
70–120 days
🧪 Soil pH
Needs 5–6.5 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 7a
📆 Growing Season
122 days in Coconino County
Growing Tips for Potatoes in Coconino County
Direct sow Potatoes outdoors after May 28 in Coconino County when soil has warmed and frost danger has passed.
Sandy soil in Coconino County dries quickly — mulch Potatoes with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
With summer highs reaching 96°F in Coconino County, provide afternoon shade for Potatoes and water deeply in the morning.
Your 122.0-day growing season in Coconino County is tight for Potatoes (70.0-120.0 days to maturity). Start indoors and choose early-maturing varieties.
Common pests for Potatoes in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.
General growing tips
Plant seed potatoes (not grocery store potatoes) 4 inches deep in spring. Hill soil around stems as plants grow to prevent greening. Stop watering when plants die back.
Recommended Potatoes Varieties for Coconino County
Early-maturing potatoes for your season
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Potatoes in Other Locations
Frequently Asked Questions
When should I plant Potatoes in Coconino County, AZ?
Coconino County is in Zone 7a with an average last frost of May 28. Plan your Potatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Coconino County, AZ?
Coconino County, Arizona is in USDA Hardiness Zone 7a. The average last spring frost is May 28 and first fall frost is September 27.
Your Coconino County Garden Planner — Free
A 24-page printable planner built for Coconino County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.