When to Plant Radicchio in Coconino County, AZ
Top priorities for Coconino County, Arizona gardeners in May
Your garden in Coconino County, Arizona is working on a schedule, even when you're not. Here's where you should be this May.
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Get radicchio in the ground
Your last frost (May 28) has passed. These warm-season crops can handle outdoor soil now.
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Plant radicchio from seed, right in the garden
Sow every 2 weeks for a continuous harvest. A single big planting means a single big glut.
Radicchio is an Italian chicory with stunning red and white leaves and a pleasantly bitter flavor. It forms tight heads and is used in salads, grilled, or braised.
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 Radicchio may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Radicchio will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Radicchio 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 Radicchio's growing requirements.
Soil pH
Your soil pH (7.2–8.6) is more alkaline than Radicchio prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
Sandy soil in Coconino County warms quickly in spring but drains fast. Radicchio will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Radicchio.
Organic Matter
Organic matter is low (0.8%). Add 2-3 inches of compost before planting Radicchio.
How to Plant Radicchio
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Radicchio
Sow every 6.9 weeks. Last sowing by Jul 09 to harvest before frost.
For a dedicated fall crop, sow by Jul 19.
Plant Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Radicchio
Radicchio needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Radicchio 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 | 3" | 0.3" | 2.7" | 🚿 Regular watering |
| Jun | 3" | 0.4" | 2.6" | 🚿 Regular watering |
| Jul | 3" | 2.6" | 0.4" | 💧 Light watering |
| Aug | 3" | 3" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 1.7" | 1.3" | 💧 Light 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.
Radicchio 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.
Radicchio Planting Timeline — Coconino County, AZ
Radicchio Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 23 | Apr 23 – May 7 |
| Transplant Outdoors | May 28 | May 28 – Jun 11 |
| Direct Sow | May 14 | May 14 – Jun 4 |
| Harvest | July 30 | Jul 30 – Sep 3 |
| Fall Sowing | July 19 | Jul 19 – Aug 2 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Fall Sowing Harvest |
| August | Fall Sowing Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.7"/week · 1-2 times/week
📅 Days to Maturity
60–80 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 7a
📆 Growing Season
122 days in Coconino County
Growing Tips for Radicchio in Coconino County
Direct sow Radicchio outdoors after May 28 in Coconino County when soil has warmed and frost danger has passed.
Sandy soil in Coconino County dries quickly — mulch Radicchio 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 Radicchio and water deeply in the morning.
Common pests for Radicchio in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Start in late summer for fall harvest. The red color develops with cool nights and light frost. Harvest when heads are firm and compact.
Companion Planting
Good Companions
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Check more plant combinations with our Companion Planting Checker →
Radicchio in Other Locations
Frequently Asked Questions
When should I plant Radicchio in Coconino County, AZ?
Coconino County is in Zone 7a with an average last frost of May 28. Plan your Radicchio 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.