When to plant Radish in Sumner, IL
Sumner sits in USDA Zone 6b. Plant Radish between March 30 (after last frost on April 13) and April 20. A second sowing from August 18 to September 1 extends the harvest into fall.
When to Plant Radish in Sumner, IL
June to-do list for Lawrence County, Illinois
Your Lawrence County, Illinois garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.
Radishes are one of the fastest-growing vegetables, with some varieties ready in under a month. They come in round, elongated, and large winter types.
Sumner, Illinois is in USDA Zone 6b. The average last spring frost is April 13 and the first fall frost is October 27, giving you a growing season of approximately 197 days.
At an elevation of 969 feet, Lawrence County receives approximately 35.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Radish during the growing season.
Sumner Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-7.3
Drainage
Well Drained
Radish Planting Risk Windows
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 Sumner
How your county's soil matches Radish's growing requirements.
Soil pH
Your soil pH (5.8–7.3) overlaps with Radish's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Lawrence County is excellent for Radish — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.9%). Annual compost additions will help Radish.
How to Plant Radish
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Radish
Sow every 2.4 weeks. Last sowing by Sep 22 to harvest before frost.
For a dedicated fall crop, sow by Aug 18.
Radish Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Radish
Radish needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Radish Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 2.6" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 1.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Lawrence County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Radish 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.
Radish Planting Timeline — Sumner, IL
Radish Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | March 30 | Mar 30 – Apr 20 |
| Harvest | April 27 | Apr 27 – May 18 |
| Fall Sowing | August 18 | Aug 18 – Sep 1 |
Plant 0.5" deep · 2" apart · Rows 6" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Direct Sow |
| April | Direct Sow Harvest |
| May | Harvest |
| June | — |
| July | — |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
22–35 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
197 days in Lawrence County
Growing Tips for Radish in Sumner
Direct sow Radish outdoors after April 13 in Lawrence County when soil has warmed and frost danger has passed.
Your generous 197.0-day season in Lawrence County allows multiple plantings of Radish. Sow every 11.0 days for continuous harvest.
Common pests for Radish 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 every 1-2 weeks for continuous harvest. Do not transplant. Harvest spring radishes promptly to prevent them from becoming pithy and hot.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Radish in Other Locations
When should I plant Radish in Sumner, IL?
In Sumner, IL, plant Radish after the last frost (around April 13) and before the first frost (around October 27). Best results when soil holds above 50°F.
What growing zone is Sumner, IL for Radish?
Sumner sits in USDA Zone 6b. Radish grows reliably in zones 2a through 11b, so it's a good fit here.
Can Radish grow in Sumner's climate?
Yes — Radish grows well in Sumner's temperate climate. Sumner averages a 197-day frost-free season, with last frost around April 13 and first frost around October 27.
Your Lawrence County Garden Planner — Free
A 22-page printable planner built for Lawrence County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.