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When to Plant Radicchio in Jackson County, SD

Jackson County, South Dakota Zone 5a May

May in Jackson County, South Dakota — your action list

A quick May briefing for Jackson County, South Dakota gardeners — what's urgent, what's next, and what can wait.

Avg. last frost May 14
Avg. first frost September 28
Soil temp (4") 55°F
Watering High
Pest pressure Low
Daylight 14.5 hrs
  1. Set out radicchio seedlings

    Pick a cloudy afternoon or evening to plant. Less transplant shock, and your seedlings will barely blink.

Looking ahead to June
  • Starting indoors: 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.

Jackson County, South Dakota is in USDA Zone 5a. The average last spring frost is May 14 and the first fall frost is September 28, giving you a growing season of approximately 137 days.

At an elevation of 1,001 feet, Jackson County receives approximately 20.1 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Radicchio to ensure they mature before fall.

Jackson County, SD (Zone 5a) Short season
137 days
Last Spring Frost May 14
137 growing days
First Fall Frost September 28

Jackson County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (37 days to spare)
Start indoors: Apr 4 Transplant: May 9 🍅 Harvest: Jul 11 – Aug 15
Recommended (50%) ✓ Fits season (39 days to spare)
Start indoors: Apr 9 Transplant: May 14 🍅 Harvest: Jul 16 – Aug 20
Safe Start (90%) ✓ Fits season (36 days to spare)
Start indoors: Apr 21 Transplant: May 26 🍅 Harvest: Jul 28 – Sep 1

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 Jackson County

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

Soil pH

Your soil pH (6.4–7.8) is more alkaline than Radicchio prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.8%). 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

2
successive plantings in your 137-day season

Sow every 6.9 weeks. Last sowing by Jul 10 to harvest before frost.

For a dedicated fall crop, sow by Jul 20.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.6″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 123 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 1.4" 0" ❄️ Dormant
Feb 1" 0" ❄️ Dormant
Mar 1.9" 0" ❄️ Dormant
Apr 2.3" 0" ❄️ Dormant
May 3" 2.4" 0.6" 💧 Light watering
Jun 3" 1.5" 1.5" 🚿 Regular watering
Jul 3" 1.9" 1.1" 💧 Light watering
Aug 3" 1.9" 1.1" 💧 Light watering
Sep 3" 1.6" 1.4" 💧 Light watering
Oct 1.7" 0" ❄️ Dormant
Nov 1.2" 0" ❄️ Dormant
Dec 1.2" 0" ❄️ Dormant

Water needs are for active growing months only (May–Sep in Jackson 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 ~700 GDD — county provides 1,370 GDD Excellent fit

Radicchio Planting Timeline — Jackson County, SD

Radicchio Planting Calendar

Activity When Date Range
Start Indoors April 9 Apr 9 – Apr 23
Transplant Outdoors May 14 May 14 – May 28
Direct Sow April 30 Apr 30 – May 21
Harvest July 16 Jul 16 – Aug 20
Fall Sowing July 20 Jul 20 – Aug 3

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

Month-by-Month Timeline

MonthActivities
January
February
March
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
June
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 5a

📆 Growing Season

137 days in Jackson County

Growing Tips for Radicchio in Jackson County

Direct sow Radicchio outdoors after May 14 in Jackson 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 Jackson County, SD?

Jackson County is in Zone 5a with an average last frost of May 14. Plan your Radicchio planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jackson County, SD?

Jackson County, South Dakota is in USDA Hardiness Zone 5a. The average last spring frost is May 14 and first fall frost is September 28.

🌱

Your Jackson County Garden Planner — Free

A 24-page printable planner built for Jackson County (Zone 5a). 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 Jackson County, SD. Local conditions may vary. Last updated: May 2026.

Sources & credits

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