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When to Plant Radicchio in Crowley County, CO

Crowley County, Colorado Zone 5b May

This month in Crowley County, Colorado

We've pulled the most time-sensitive tasks for Crowley County, Colorado this May and put them front and centre. Tackle them in order.

Avg. last frost April 26
Avg. first frost October 9
Soil temp (4") 47°F
Watering High
Pest pressure Low
Daylight 14.1 hrs
  1. Time to start radicchio inside

    Label every cell. You will absolutely forget which is which otherwise.

A few tasks this May that'll pay off in June
  • First harvests: radicchio

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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.

Crowley County, Colorado is in USDA Zone 5b. The average last spring frost is April 26 and the first fall frost is October 9, giving you a growing season of approximately 166 days.

At an elevation of 5,963 feet, Crowley County receives approximately 17.8 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Radicchio during the growing season. With low rainfall, drip irrigation is essential for growing Radicchio successfully. Mulch heavily to conserve soil moisture.

Crowley County, CO (Zone 5b) Moderate season
166 days
Last Spring Frost April 26
166 growing days
First Fall Frost October 9

Crowley County Soil Profile

Soil Type

Loam

Soil pH

6.6-7.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (69 days to spare)
Start indoors: Mar 17 Transplant: Apr 21 🍅 Harvest: Jun 23 – Jul 28
Recommended (50%) ✓ Fits season (68 days to spare)
Start indoors: Mar 22 Transplant: Apr 26 🍅 Harvest: Jun 28 – Aug 2
Safe Start (90%) ✓ Fits season (66 days to spare)
Start indoors: Apr 7 Transplant: May 12 🍅 Harvest: Jul 14 – Aug 18

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 Crowley County

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

Soil pH

Your soil pH (6.6–7.6) is more alkaline than Radicchio prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Crowley County is excellent for Radicchio — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Radicchio.

How to Plant Radicchio

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

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

Succession Planting Radicchio

3
successive plantings in your 166-day season

Sow every 6.9 weeks. Last sowing by Jul 21 to harvest before frost.

For a dedicated fall crop, sow by Jul 31.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.5″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 443 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — 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 1.3" 0" ❄️ Dormant
Feb 1" 0" ❄️ Dormant
Mar 1.5" 0" ❄️ Dormant
Apr 3" 1.8" 1.2" 💧 Light watering
May 3" 2.2" 0.8" 💧 Light watering
Jun 3" 1.3" 1.7" 🚿 Regular watering
Jul 3" 1.6" 1.4" 💧 Light watering
Aug 3" 2.1" 0.9" 💧 Light watering
Sep 3" 1.3" 1.7" 🚿 Regular watering
Oct 3" 1.4" 1.6" 🚿 Regular watering
Nov 1.2" 0" ❄️ Dormant
Dec 1.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Crowley 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 needs ~1,225 GDD — county provides 2,905 GDD Excellent fit

Radicchio Planting Timeline — Crowley County, CO

Radicchio Planting Calendar

Activity When Date Range
Start Indoors March 22 Mar 22 – Apr 5
Transplant Outdoors April 26 Apr 26 – May 10
Direct Sow April 12 Apr 12 – May 3
Harvest June 28 Jun 28 – Aug 2
Fall Sowing July 31 Jul 31 – Aug 14

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.7"/week · Only during dry spells

📅 Days to Maturity

60–80 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 5b

📆 Growing Season

166 days in Crowley County

Growing Tips for Radicchio in Crowley County

Direct sow Radicchio outdoors after April 26 in Crowley County when soil has warmed and frost danger has passed.

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

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Radicchio in Crowley County, CO?

Crowley County is in Zone 5b with an average last frost of April 26. Plan your Radicchio planting based on this frost date — see the calendar above for exact timing.

What planting zone is Crowley County, CO?

Crowley County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is April 26 and first fall frost is October 9.

🌱

Your Crowley County Garden Planner — Free

A 24-page printable planner built for Crowley County (Zone 5b). 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 Crowley County, CO. 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.