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When to Plant Radish in USDA Zone 5b

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 5b, the average last spring frost is around April 18 and the first fall frost is around October 13, giving you a growing season of approximately 178 days.

Zone 5b Moderate season
178 days
Last Spring Frost April 18
178 growing days
First Fall Frost October 13

Radish Planting Timeline — Zone 5b

Where Is USDA Zone 5b?

The map below highlights the states that contain Zone 5b. Click any state to see the Radish planting schedule for that location.

Prints a clean, ink-friendly version without maps or navigation.

Radish Planting Calendar — Zone 5b

Activity When Date Range
Direct Sow April 4 Apr 4 – Apr 25
Fall Sowing August 4 Aug 4 – Aug 18
Harvest May 2 May 2 – May 23

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

Month-by-Month Timeline

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

Free Zone 5b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 5b with start dates, transplant windows, and harvest times.

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Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate — regular watering

Days to Maturity

22–35 days

Soil pH

6 – 7

Zone Temperature Range

-15°F to -10°F average annual minimum

Growing Season

178 days (Zone 5b average)

Planting Specifications

Planting Depth0.5 inches
Plant Spacing2 inches apart
Row Spacing6 inches between rows

Growing Tips for Zone 5b

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

Level Up Your Garden

Saving Radish Seeds

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Frequently Asked Questions

When should I plant Radish in Zone 5b?

In Zone 5b, plan your Radish planting around the average last frost date of April 18. Direct sow outdoors around April 4.

Can Radish grow in Zone 5b?

Yes, Radish can grow well in Zone 5b, hardy in USDA zones 2a through 11b. Zone 5b has a growing season of approximately 178 days, which is sufficient for Radish (22-35 days to maturity).

When can I harvest Radish in Zone 5b?

In Zone 5b, expect to harvest Radish from May 2 – May 23. Radish takes 22-35 days from planting to harvest.

What is the last frost date for Zone 5b?

The average last spring frost in Zone 5b is around April 18, and the first fall frost is around October 13. This gives a growing season of approximately 178 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.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner — organize your planting dates for Zone 5b, track your crops, and plan your garden season from seed to harvest.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: April 2026.