One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By using the USDA zone info for Swarthmore it's a good idea to estimate when it's the best time to plant radishes.

Planting Calendar for Radishes

Frost tolerance for radishes:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Radishes can survive in cold weather which tells us that you can plant them earlier in the year than more sensitive plants.

The earliest that you can plant radishes in Swarthmore is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant radishes and expect a good harvest is probably September. Any later than that and your radishes may not have a chance to fully mature. Starting your radishes indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Swarthmore the average date of last frost happens on April 15. You can expect an average low temperature of 0°F in the coldest months of winter.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Swarthmore and it will vary from year to year. Since half of the time in Swarthmore last frost occurs after April 15 be ready to protect your radishes in the event of a surprise late frost.

USDA Zone Info for Swarthmore

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Swarthmore

You may be interested in your other planting guides for Swarthmore.