The USDA Zone info is a great tool for gardeners to help us estimate 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.

The USDA zone info for Princeton should be read to determine when to plant bishop's weed.

Planting Calendar for Bishop's Weed

Frost tolerance for bishop's weed:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Bishop's Weed do well in a bit of cold which means that you can plant them a lot earlier in the year than other plants that might not handle the cold.

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

The last month that you can plant bishop's weed and expect a good harvest is probably August. Any later than that and your bishop's weed may not have a chance to fully mature. If you are starting your bishop's weed indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Princeton. It might get as low as -30°F during the coldest months of winter.

It's important to remember that USDA zone info for Princeton may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Princeton last frost occurs after May 15 so always be ready to protect your bishop's weed if you have one of those late frosts.

USDA Zone Info for Princeton

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Princeton

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