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When to Plant Radicchio in Haskell County, OK

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.

Haskell County, Oklahoma is in USDA Zone 7a. The average last spring frost is March 28 and the first fall frost is November 3, giving you a growing season of approximately 220 days.

At an elevation of 691 feet, Haskell County receives approximately 29.2 inches of rainfall annually with predominantly loam soil. Summer highs average 91ยฐF, providing good warmth for Radicchio during the growing season.

Haskell County, OK (Zone 7a) Long season
220 days
Last Spring Frost March 28
220 growing days
First Fall Frost November 3

Haskell County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (122 days to spare)
Start indoors: Feb 14 Transplant: Mar 21 🍅 Harvest: May 23 – Jun 27
Recommended (50%) ✓ Fits season (122 days to spare)
Start indoors: Feb 21 Transplant: Mar 28 🍅 Harvest: May 30 – Jul 4
Safe Start (90%) ✓ Fits season (125 days to spare)
Start indoors: Mar 10 Transplant: Apr 14 🍅 Harvest: Jun 16 – Jul 21

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 Haskell County

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

Soil pH

Your soil pH (6.5โ€“7.5) overlaps with Radicchio's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

The loam soil in Haskell County is excellent for Radicchio โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.3%) โ€” Radicchio will thrive.

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

4
successive plantings in your 220-day season

Sow every 6.9 weeks. Last sowing by Aug 15 to harvest before frost.

For a dedicated fall crop, sow by Aug 25.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.6″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 335 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” 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 โ€” 0.7" 0" โ„๏ธ Dormant
Feb โ€” 1.1" 0" โ„๏ธ Dormant
Mar 3" 1.9" 1.1" ๐Ÿ’ง Light watering
Apr 3" 2.9" 0.1" ๐Ÿ’ง Light watering
May 3" 4" 0" โœ… Rainfall sufficient
Jun 3" 4.8" 0" โœ… Rainfall sufficient
Jul 3" 3.8" 0" โœ… Rainfall sufficient
Aug 3" 3" 0" โœ… Rainfall sufficient
Sep 3" 3.1" 0" โœ… Rainfall sufficient
Oct 3" 2.1" 0.9" ๐Ÿ’ง Light watering
Nov 3" 1" 2" ๐Ÿšฟ Regular watering
Dec โ€” 0.7" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Haskell County). Supplement amounts are based on average rainfall โ€” 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" 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.

Radicchio needs ~1,278 GDD — county provides 4,015 GDD Excellent fit

Radicchio Planting Timeline โ€” Haskell County, OK

Radicchio Planting Calendar

Activity When Date Range
Start Indoors February 21 Feb 21 โ€“ Mar 7
Transplant Outdoors March 28 Mar 28 โ€“ Apr 11
Direct Sow March 14 Mar 14 โ€“ Apr 4
Harvest May 30 May 30 โ€“ Jul 4
Fall Sowing August 25 Aug 25 โ€“ Sep 8

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.7"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

60โ€“80 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

220 days in Haskell County

Growing Tips for Radicchio in Haskell County

Direct sow Radicchio outdoors after March 28 in Haskell 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 Haskell County, OK?

Haskell County is in Zone 7a with an average last frost of March 28. Plan your Radicchio planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Haskell County, OK?

Haskell County, Oklahoma is in USDA Hardiness Zone 7a. The average last spring frost is March 28 and first fall frost is November 3.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Haskell County gardeners in Zone 7a 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 Haskell County, OK. Local conditions may vary. Last updated: April 2026.