The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can figure out when it's possible to plant calliopsis in Princeton by reviewing the USDA zone info.

Planting Calendar for Calliopsis

Frost tolerance for calliopsis:	Not tolerant of frost.
When to plant:	After the last frost.

It's probably not a good idea to plant calliopsis until after the last frost has passed because they require warm weather.

The earliest that you can plant calliopsis in Princeton is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant calliopsis and expect a good harvest is probably August. Any later than that and your calliopsis may not have a chance to grow to maturity. If you are starting your calliopsis indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

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

Since the USDA zone info for Princeton may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Princeton last frost occurs after April 15 so always be ready to cover your calliopsis if you have one of those late frosts.

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.