One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to determine when to plant peonies by reviewing the USDA zone info for Princeton.

Planting Calendar for Peonies

Frost tolerance for peonies:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant peonies slightly earlier in the year because they are barely cold tolerant.

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

Last Frost Date

In Princeton the average date of last frost happens on May 15. In the coldest months of winter you can expect an average low temperature of -30°F.

It's important to remember that USDA zone info for Princeton is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Princeton you get surprised by a frost after May 15 so always be ready to cover your peonies if you have a surprise late frost.

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.