Root Vegetable

When to Plant Radishes in Pennsylvania

The fastest vegetable in the garden — some varieties are ready in just 25 days. Perfect for impatient gardeners and kids.

The Short Answer

Radishes are the first and fastest crop in the Pennsylvania spring garden — some gardeners plant them on St. Patrick's Day and harvest by tax day.

Pennsylvania Frost Dates

Your planting dates depend on which part of Pennsylvania you're in. Here are the frost date ranges by region:

Region Zones Last Frost (Spring) First Frost (Fall)
Northern Pennsylvania 5a, 5b, 6a May 5 - May 20 Sep 20 - Oct 5
Central Pennsylvania 5b, 6a, 6b Apr 25 - May 10 Oct 1 - Oct 15
Philadelphia Region 7a, 7b Apr 5 - Apr 20 Oct 15 - Nov 5

Radishes Planting Schedule for Pennsylvania

Northern Pennsylvania (Zones 5a, 5b, 6a)

Average last frost: May 5 - May 20 · Average first frost: Sep 20 - Oct 5

Direct Sow
4 wks before frost
Fall Planting
6 wks before first frost

Central Pennsylvania (Zones 5b, 6a, 6b)

Average last frost: Apr 25 - May 10 · Average first frost: Oct 1 - Oct 15

Direct Sow
4 wks before frost
Fall Planting
6 wks before first frost

Philadelphia Region (Zones 7a, 7b)

Average last frost: Apr 5 - Apr 20 · Average first frost: Oct 15 - Nov 5

Direct Sow
4 wks before frost
Fall Planting
6 wks before first frost

Growing Radishes in Pennsylvania

State-Specific Growing Tips

Direct sow from late March. Succession plant every 2 weeks through May. Fall sowing in August-September. Pennsylvania's varied soils all grow radishes well. Penn State Extension considers radishes the perfect first-time gardener crop.

Recommended Varieties for Pennsylvania

Cherry Belle, French Breakfast, Easter Egg. Watermelon radish for fall. Daikon for storage.

Common Challenges in Pennsylvania

Flea beetles. Root maggots occasionally. Bolting in June-July heat. The crop is nearly foolproof in Pennsylvania's cool springs.

Growing Tips

Don't let them stay in the ground too long — they get pithy and hot. Succession plant every 2 weeks for continuous harvest.

Companion Planting

Plant radishes alongside these companions for better growth:

Peas Lettuce Carrots Spinach

The Bottom Line

Radishes can be grown successfully in Pennsylvania with proper attention to regional frost dates and local growing conditions. Timing varies across the state — Northern Pennsylvania gardeners work with a last frost around May 5 - May 20, while Philadelphia Region sees frost end around Apr 5 - Apr 20. Choose varieties suited to your region, amend your soil based on its specific needs, and monitor for the pests and diseases most common in your area. For exact dates based on your zip code, use our free planting date finder.

Related Guides

Radishes Growing Guide National planting guide with all states Pennsylvania Planting Calendar All plants for Pennsylvania Radishes in Alabama Alabama planting dates Radishes in Alaska Alaska planting dates Radishes in Arizona Arizona planting dates Radishes in Arkansas Arkansas planting dates
Note: All dates are based on NOAA 30-year Climate Normals and represent historical averages, not predictions for any specific year. Always check your local weather forecast before planting frost-sensitive crops. Learn about our data sources.

Last reviewed: March 29, 2026

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