When to Plant Radish in New London County, CT
What to do in May
We've pulled the most time-sensitive tasks for New London County, Connecticut this May and put them front and centre. Tackle them in order.
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Harvest radish as they ripen
If you can't use it all right away, check the food-preservation section of your planner.
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.
New London County, Connecticut is in USDA Zone 7a. The average last spring frost is April 23 and the first fall frost is October 18, giving you a growing season of approximately 178 days.
At an elevation of 766 feet, New London County receives approximately 49.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Radish during the growing season.
New London County Soil Profile
Soil Type
Silt Loam
Soil pH
5-6.6
Drainage
Well Drained
Plant 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 New London County
How your county's soil matches Radish's growing requirements.
Soil pH
Your soil pH (5.0–6.6) is more acidic than Radish prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in New London County is excellent for Radish — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Radish.
Organic Matter
Organic matter is moderate (3.6%). 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 13 to harvest before frost.
For a dedicated fall crop, sow by Aug 09.
Plant Water Budget
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 | — | 3.5" | 0" | ❄️ Dormant |
| Feb | — | 3.5" | 0" | ❄️ Dormant |
| Mar | — | 4" | 0" | ❄️ Dormant |
| Apr | 2.2" | 4.7" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 5.1" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Nov | — | 3.9" | 0" | ❄️ Dormant |
| Dec | — | 3.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in New London 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 — New London County, CT
Radish Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | April 9 | Apr 9 – Apr 30 |
| Harvest | May 7 | May 7 – May 28 |
| Fall Sowing | August 9 | Aug 9 – Aug 23 |
Plant 0.5" deep · 2" apart · Rows 6" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Direct Sow |
| May | Harvest |
| June | — |
| July | — |
| August | Fall Sowing |
| September | — |
| 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: too_acidic
🗺️ USDA Zone
Zone 7a
📆 Growing Season
178 days in New London County
Growing Tips for Radish in New London County
Direct sow Radish outdoors after April 23 in New London County when soil has warmed and frost danger has passed.
Your generous 178.0-day season in New London 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
Frequently Asked Questions
When should I plant Radish in New London County, CT?
New London County is in Zone 7a with an average last frost of April 23. Plan your Radish planting based on this frost date — see the calendar above for exact timing.
What planting zone is New London County, CT?
New London County, Connecticut is in USDA Hardiness Zone 7a. The average last spring frost is April 23 and first fall frost is October 18.
Your New London County Garden Planner — Free
A 24-page printable planner built for New London 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.