Blog

When to Plant Radicchio in Mower County, MN

Mower County, Minnesota Zone 4b May

Top priorities for Mower County, Minnesota gardeners in May

A quick May briefing for Mower County, Minnesota gardeners — what's urgent, what's next, and what can wait.

Avg. last frost April 28
Avg. first frost October 7
Soil temp (4") 53°F
Watering Moderate
Pest pressure Low
Daylight 14.5 hrs
Get ahead of June
  • Starting indoors: radicchio
  • First harvests: radicchio

Instant PDF download. No spam, unsubscribe any time.

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.

Mower County, Minnesota is in USDA Zone 4b. The average last spring frost is April 28 and the first fall frost is October 7, giving you a growing season of approximately 162 days.

At an elevation of 577 feet, Mower County receives approximately 33 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Radicchio to ensure they mature before fall.

Mower County, MN (Zone 4b) Moderate season
162 days
Last Spring Frost April 28
162 growing days
First Fall Frost October 7
Share this guide:

Mower County Soil Profile

Soil Type

Silt Loam

Soil pH

6.3-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (61 days to spare)
Start indoors: Mar 13 Transplant: Apr 24 🍅 Harvest: Jun 26 – Jul 31
Recommended (50%) ✓ Fits season (64 days to spare)
Start indoors: Mar 17 Transplant: Apr 28 🍅 Harvest: Jun 30 – Aug 4
Safe Start (90%) ✓ Fits season (57 days to spare)
Start indoors: Apr 2 Transplant: May 14 🍅 Harvest: Jul 16 – Aug 20

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 Mower County

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

Soil pH

Your soil pH (6.3–6.7) is within Radicchio's preferred range (6.0–7.0).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.6%) — Radicchio will thrive.

How to Plant Radicchio

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

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Succession Planting Radicchio

3
successive plantings in your 162-day season

Sow every 6.9 weeks. Last sowing by Jul 19 to harvest before frost.

For a dedicated fall crop, sow by Jul 15.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

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 1.6" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 3" 3.7" 0" ✅ Rainfall sufficient
May 3" 3.4" 0" ✅ Rainfall sufficient
Jun 3" 3.9" 0" ✅ Rainfall sufficient
Jul 3" 3.3" 0" ✅ Rainfall sufficient
Aug 3" 3.6" 0" ✅ Rainfall sufficient
Sep 3" 2.8" 0.2" 💧 Light watering
Oct 3" 2.4" 0.6" 💧 Light watering
Nov 2.5" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Mower 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 ~805 GDD — county provides 1,863 GDD Excellent fit

Radicchio Planting Timeline — Mower County, MN

Radicchio Planting Calendar

Activity When Date Range
Start Indoors March 17 Mar 17 – Mar 31
Transplant Outdoors April 28 Apr 28 – May 12
Direct Sow April 21 Apr 21 – May 12
Harvest June 30 Jun 30 – Aug 4
Fall Sowing July 15 Jul 15 – Jul 29

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.7"/week · Natural rainfall sufficient

📅 Days to Maturity

60–80 days

🧪 Soil pH

Needs 6–7 · Your soil: ideal

🗺️ USDA Zone

Zone 4b

📆 Growing Season

162 days in Mower County

Growing Tips for Radicchio in Mower County

Direct sow Radicchio outdoors after April 28 in Mower 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 Mower County, MN?

Mower County is in Zone 4b with an average last frost of April 28. Plan your Radicchio planting based on this frost date — see the calendar above for exact timing.

What planting zone is Mower County, MN?

Mower County, Minnesota is in USDA Hardiness Zone 4b. The average last spring frost is April 28 and first fall frost is October 7.

🌱

Your Mower County Garden Planner — Free

A 24-page printable planner built for Mower County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Mower County, MN. 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.