One of the best tools that you have as gardeners to help us determine 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.

It's a good idea to figure out when you can plant radicchio by referring to the USDA zone info for Princeton.

Planting Calendar for Radicchio

Frost tolerance for radicchio:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Radicchio do well in moderate cold which tells us that you can get them planted earlier than plants that are more sensitive to the cold.

The earliest that you can plant radicchio in Princeton 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 radicchio and expect a good harvest is probably September. You probably don't want to wait any later than that or else your radicchio may not have a chance to fully mature. If you are starting your radicchio indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Princeton. In the coldest months of winter you can expect an average low temperature of -5°F.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Princeton and it will vary from year to year. Half of the time in Princeton last frost occurs after April 15 so just be sure to be ready to protect your radicchio in the event of a surprise late frost.

USDA Zone Info for Princeton

Here is the info for USDA Zone 6b.

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

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

Plants to Grow in Princeton

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