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When to Plant Broccoli Rabe in Madison County, IL

Madison County, Illinois Zone 7a May

Your May gardening checklist

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

Avg. last frost April 11
Avg. first frost October 22
Soil temp (4") 61°F
Watering Moderate
Pest pressure Low
Daylight 14.1 hrs
  1. Time to start broccoli rabe inside

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

  2. Collect broccoli rabe at their peak

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

Before June arrives, get these ready
  • First harvests: broccoli rabe

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Broccoli rabe (rapini) is a brassica grown for its slightly bitter, nutty-flavored florets, leaves, and stems. It is a staple in Italian cooking.

Madison County, Illinois is in USDA Zone 7a. The average last spring frost is April 11 and the first fall frost is October 22, giving you a growing season of approximately 194 days.

At an elevation of 963 feet, Madison County receives approximately 36.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Broccoli Rabe during the growing season.

Madison County, IL (Zone 7a) Moderate season
194 days
Last Spring Frost April 11
194 growing days
First Fall Frost October 22

Madison County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (119 days to spare)
Start indoors: Feb 28 Transplant: Apr 4 🍅 Harvest: May 16 – Jun 20
Recommended (50%) ✓ Fits season (117 days to spare)
Start indoors: Mar 7 Transplant: Apr 11 🍅 Harvest: May 23 – Jun 27
Safe Start (90%) ✓ Fits season (122 days to spare)
Start indoors: Mar 16 Transplant: Apr 20 🍅 Harvest: Jun 1 – Jul 6

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 Madison County

How your county's soil matches Broccoli Rabe's growing requirements.

Soil pH

Your soil pH (5.8–6.9) overlaps with Broccoli Rabe's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.8%) — Broccoli Rabe will thrive.

How to Plant Broccoli Rabe

1"
Planting Depth
15"
Between Plants
24"
Between Rows

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

Succession Planting Broccoli Rabe

5
successive plantings in your 194-day season

Sow every 4.6 weeks. Last sowing by Aug 23 to harvest before frost.

For a dedicated fall crop, sow by Aug 13.

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.8″/week
Watering frequency Only during dry spells
Season total 7 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Broccoli Rabe

Broccoli Rabe needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Broccoli Rabe Needs Rainfall You Supplement Action
Jan 1.3" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.4" 0" ❄️ Dormant
Apr 3.5" 4" 0" ✅ Rainfall sufficient
May 3.5" 3.6" 0" ✅ Rainfall sufficient
Jun 3.5" 5" 0" ✅ Rainfall sufficient
Jul 3.5" 4.1" 0" ✅ Rainfall sufficient
Aug 3.5" 4.1" 0" ✅ Rainfall sufficient
Sep 3.5" 3.4" 0.1" 💧 Light watering
Oct 3.5" 2.8" 0.7" 💧 Light watering
Nov 2.8" 0" ❄️ Dormant
Dec 1.7" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Madison County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Broccoli Rabe 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.

Broccoli Rabe needs ~838 GDD — county provides 3,249 GDD Excellent fit

Broccoli Rabe Planting Timeline — Madison County, IL

Broccoli Rabe Planting Calendar

Activity When Date Range
Start Indoors March 7 Mar 7 – Mar 21
Transplant Outdoors April 11 Apr 11 – Apr 25
Direct Sow March 28 Mar 28 – Apr 18
Harvest May 23 May 23 – Jun 27
Fall Sowing August 13 Aug 13 – Aug 27

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.8"/week · Only during dry spells

📅 Days to Maturity

40–60 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

194 days in Madison County

Growing Tips for Broccoli Rabe in Madison County

Direct sow Broccoli Rabe outdoors after April 11 in Madison County when soil has warmed and frost danger has passed.

Your generous 194.0-day season in Madison County allows multiple plantings of Broccoli Rabe. Sow every 20.0 days for continuous harvest.

Common pests for Broccoli Rabe in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow in spring or fall. Harvest when small yellow flower buds first appear but before they open. Cut the main shoot first to encourage side shoots.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Broccoli Rabe in Madison County, IL?

Madison County is in Zone 7a with an average last frost of April 11. Plan your Broccoli Rabe planting based on this frost date — see the calendar above for exact timing.

What planting zone is Madison County, IL?

Madison County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 11 and first fall frost is October 22.

🌱

Your Madison County Garden Planner — Free

A 24-page printable planner built for Madison 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.

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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 Madison County, IL. 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.