One of the first steps you take when you are figuring out your gardening schedule is find your 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 referring to the USDA zone info for Princeton it's a good idea to figure out when you can plant calendula.

Planting Calendar for Calendula

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

You can plant calendula a bit earlier in the year because they do well in moderate cold.

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

Since the USDA zone info for Princeton is just an average the actual date of last frost changes from year to year. Since half of the time in Princeton last frost occurs after April 15 be ready to cover your calendula if you have 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.