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.

The USDA zone info for Harvard can be read to estimate when it's possible 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 are one of those plants that can tolerate quite a bit of cold weather which means that you can plant them much earlier than other frost tender plants.

The earliest that you can plant radishes in Harvard 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. You can get started a few weeks earlier by starting your radishes indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Harvard. You can expect an average low temperature of -15°F in the coldest months of winter.

Remember that USDA zone info for Harvard is an average and the actual date of last frost is different every year. Since half of the time in Harvard last frost occurs after April 15 be ready to protect your radishes if you have one of those late frosts.

USDA Zone Info for Harvard

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Harvard

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