When to Plant Radish in USDA Zone 4a
Your July planting checklist for Zone 4a
July is a pivotal month for Zone 4a gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Plant your fall garden: radish
Fall crops get sweeter with a light frost. Don't be afraid of cool nights.
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.
In Zone 4a, the average last spring frost is around May 6 and the first fall frost is around September 28, giving you a growing season of approximately 145 days.
Radish Planting Timeline — Zone 4a
Where Is USDA Zone 4a?
The map below highlights the states that contain Zone 4a. Click any state to see the Radish planting schedule for that location.
Radish Planting Calendar — Zone 4a
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | April 29 | Apr 29 – May 20 |
| Harvest | May 27 | May 27 – Jun 17 |
| Fall Sowing | July 6 | Jul 6 – Jul 20 |
Plant 0.5" deep · 2" apart · Rows 6" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Direct Sow |
| May | Direct Sow Harvest |
| June | Harvest |
| July | Fall Sowing |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Free Zone 4a Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 4a with start dates, transplant windows, and harvest times.
Growing Conditions
Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Moderate — regular watering
Days to Maturity
22–35 days
Soil pH
6 – 7
Zone Temperature Range
-30°F to -25°F average annual minimum
Growing Season
145 days (Zone 4a average)
Planting Specifications
| Planting Depth | 0.5 inches |
| Plant Spacing | 2 inches apart |
| Row Spacing | 6 inches between rows |
Succession Planting Radish in Zone 4a
Sow every 2.4 weeks for continuous harvest throughout the season.
Growing Tips for Radish in Zone 4a
Zone 4a has a short growing season (~145 days). Start Radish indoors early and use season-extension techniques like row covers and cold frames.
Radish needs approximately 0.5 inches of water per week during active growth. Adjust watering based on your local rainfall and soil drainage.
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
The Gardener's Encyclopedia to Companion Planting
The pairings that make vegetables, herbs, and flowers grow better — and the ones that quietly wreck a bed.
- Proven pairings for 200+ vegetables, herbs, flowers, and fruits
- Full seed-starting + planting schedule with timing and spacing
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Saving Radish Seeds
Recommended for Your Garden
Full-spectrum LED lights for starting seeds indoors when daylight is limited.
Warm soil for faster germination of heat-loving crops like tomatoes and peppers.
Protect plants from frost, wind, and pests while letting light and water through.
Related Plants
Radish in Other Zones
Radish by State
- Alabama
- Alaska
- Arizona
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Ohio
- Oklahoma
- Oregon
- Pennsylvania
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
Frequently Asked Questions
When should I plant Radish in Zone 4a?
In Zone 4a, plan your Radish planting around the average last frost date of May 6. Direct sow outdoors around April 29.
Can Radish grow in Zone 4a?
Yes, Radish can grow well in Zone 4a, hardy in USDA zones 2a through 11b. Zone 4a has a growing season of approximately 145 days, which is sufficient for Radish (22-35 days to maturity).
When can I harvest Radish in Zone 4a?
In Zone 4a, expect to harvest Radish from May 27 – June 17. Radish takes 22-35 days from planting to harvest.
What is the last frost date for Zone 4a?
The average last spring frost in Zone 4a is around May 6, and the first fall frost is around September 28. This gives a growing season of approximately 145 days. These are 50% probability dates — actual frost dates vary year to year.
What should I plant next to Radish?
Good companion plants for Radish include Carrots, Lettuce, Peas, Spinach. These companions can help with pest control, pollination, and nutrient sharing.
Your Zone 4a Garden Planner — Free
A 22-page printable planner tailored to Zone 4a. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.