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When to Plant Radish in Prince William County, VA

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.

Prince William County, Virginia is in USDA Zone 7a. The average last spring frost is April 13 and the first fall frost is October 26, giving you a growing season of approximately 196 days.

At an elevation of 372 feet, Prince William County receives approximately 46.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89ยฐF, providing good warmth for Radish during the growing season.

Prince William County, VA (Zone 7a) Moderate season
196 days
Last Spring Frost April 13
196 growing days
First Fall Frost October 26

Prince William County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (151 days to spare)
Transplant: Apr 1 🍅 Harvest: Apr 29 – May 20
Recommended (50%) ✓ Fits season (147 days to spare)
Transplant: Apr 13 🍅 Harvest: May 11 – Jun 1
Safe Start (90%) ✓ Fits season (150 days to spare)
Transplant: May 8 🍅 Harvest: Jun 5 – Jun 26

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 Prince William County

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

Soil pH

Your soil pH (5.8โ€“7.0) overlaps with Radish's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

The silt loam soil in Prince William County is excellent for Radish โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.9%). 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

11
successive plantings in your 196-day season

Sow every 2.4 weeks. Last sowing by Sep 21 to harvest before frost.

For a dedicated fall crop, sow by Aug 17.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
1.0″/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 โ€” 4.5" 0" โ„๏ธ Dormant
Feb โ€” 4.2" 0" โ„๏ธ Dormant
Mar โ€” 3.8" 0" โ„๏ธ Dormant
Apr 2.2" 3.5" 0" โœ… Rainfall sufficient
May 2.2" 4.1" 0" โœ… Rainfall sufficient
Jun 2.2" 4.1" 0" โœ… Rainfall sufficient
Jul 2.2" 4.6" 0" โœ… Rainfall sufficient
Aug 2.2" 4.1" 0" โœ… Rainfall sufficient
Sep 2.2" 3.1" 0" โœ… Rainfall sufficient
Oct 2.2" 2.8" 0" โœ… Rainfall sufficient
Nov โ€” 3.2" 0" โ„๏ธ Dormant
Dec โ€” 4.1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Prince William County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 ~477 GDD — county provides 3,283 GDD Excellent fit

Radish Planting Timeline โ€” Prince William County, VA

Radish Planting Calendar

Activity When Date Range
Direct Sow March 30 Mar 30 โ€“ Apr 20
Harvest April 27 Apr 27 โ€“ May 18
Fall Sowing August 17 Aug 17 โ€“ Aug 31

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Direct Sow
April Direct Sow Harvest
May Harvest
June โ€”
July โ€”
August Fall Sowing
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

22โ€“35 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

196 days in Prince William County

Growing Tips for Radish in Prince William County

Direct sow Radish outdoors after April 13 in Prince William County when soil has warmed and frost danger has passed.

Your generous 196.0-day season in Prince William 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

  • Hyssop

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Radish in Prince William County, VA?

Prince William County is in Zone 7a with an average last frost of April 13. Plan your Radish planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Prince William County, VA?

Prince William County, Virginia is in USDA Hardiness Zone 7a. The average last spring frost is April 13 and first fall frost is October 26.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Prince William County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Prince William County, VA. Local conditions may vary. Last updated: April 2026.