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When to Plant Radish in Roanoke City, VA

Roanoke City, Virginia Zone 7b May

This month in Roanoke City, Virginia

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Roanoke City, Virginia.

Avg. last frost April 25
Avg. first frost October 20
Soil temp (4") 69°F
Watering Low
Pest pressure Moderate
Daylight 14 hrs
  1. Basket week: radish

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

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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.

Roanoke City, Virginia is in USDA Zone 7b. The average last spring frost is April 25 and the first fall frost is October 20, giving you a growing season of approximately 178 days.

At an elevation of 336 feet, Roanoke City receives approximately 53.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 94°F, providing good warmth for Radish during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Radish root diseases.

Roanoke City, VA (Zone 7b) Moderate season
178 days
Last Spring Frost April 25
178 growing days
First Fall Frost October 20

Roanoke City Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (132 days to spare)
Transplant: Apr 18 🍅 Harvest: May 16 – Jun 6
Recommended (50%) ✓ Fits season (129 days to spare)
Transplant: Apr 25 🍅 Harvest: May 23 – Jun 13
Safe Start (90%) ✓ Fits season (123 days to spare)
Transplant: May 14 🍅 Harvest: Jun 11 – Jul 2

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 Roanoke City

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

Soil pH

Your soil pH (5.4–6.5) is more acidic than Radish prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Roanoke City is excellent for Radish — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.2%). Annual compost additions will help Radish.

How to Plant Radish

0.5"
Planting Depth
2"
Between Plants
6"
Between Rows

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

Succession Planting Radish

10
successive plantings in your 178-day season

Sow every 2.4 weeks. Last sowing by Sep 15 to harvest before frost.

For a dedicated fall crop, sow by Aug 11.

Plant Water Budget

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

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 4.5" 0" ❄️ Dormant
Feb 4" 0" ❄️ Dormant
Mar 4.8" 0" ❄️ Dormant
Apr 2.2" 4.2" 0" ✅ Rainfall sufficient
May 2.2" 4.8" 0" ✅ Rainfall sufficient
Jun 2.2" 4.6" 0" ✅ Rainfall sufficient
Jul 2.2" 5.8" 0" ✅ Rainfall sufficient
Aug 2.2" 5.6" 0" ✅ Rainfall sufficient
Sep 2.2" 3.6" 0" ✅ Rainfall sufficient
Oct 2.2" 3.2" 0" ✅ Rainfall sufficient
Nov 4.7" 0" ❄️ Dormant
Dec 4" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Roanoke City). 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 needs ~584 GDD — county provides 3,649 GDD Excellent fit

Radish Planting Timeline — Roanoke City, VA

Radish Planting Calendar

Activity When Date Range
Direct Sow April 11 Apr 11 – May 2
Harvest May 9 May 9 – May 30
Fall Sowing August 11 Aug 11 – Aug 25

Plant 0.5" deep · 2" apart · Rows 6" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Direct Sow
May Direct Sow 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 7b

📆 Growing Season

178 days in Roanoke City

Growing Tips for Radish in Roanoke City

Direct sow Radish outdoors after April 25 in Roanoke City when soil has warmed and frost danger has passed.

Summer highs in Roanoke City reach 94°F — grow Radish as a spring or fall crop. Use shade cloth if planting in summer.

Your generous 178.0-day season in Roanoke City 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

  • Hyssop

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Radish in Roanoke City, VA?

Roanoke City is in Zone 7b with an average last frost of April 25. Plan your Radish planting based on this frost date — see the calendar above for exact timing.

What planting zone is Roanoke City, VA?

Roanoke City, Virginia is in USDA Hardiness Zone 7b. The average last spring frost is April 25 and first fall frost is October 20.

🌱

Your Roanoke City Garden Planner — Free

A 24-page printable planner built for Roanoke City (Zone 7b). 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 Roanoke City, VA. Local conditions may vary. Last updated: May 2026.

Sources & credits

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