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

In Zone 4a you can determine when it's possible to plant peonies by reviewing the USDA zone info.

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.

Peonies do ok in moderate cold which means that you can get them planted just a bit earlier than other frost tender plants.

The earliest that you can plant peonies in Zone 4a 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. If you wait any later than that and your peonies may not have a chance to fully mature. You can get started a few weeks earlier by starting your peonies indoors.

Last Frost Date

On average all chance of frost has passed is on May 15 in Zone 4a. In the coldest months of winter you should expect an average low temperature of -30°F.

Since the USDA zone info for Zone 4a is just an average the actual date of last frost is different every year. Half of the time in Zone 4a you get surprised by a frost after May 15 so make sure that you are ready to cover your peonies if you have one of those late frosts.

USDA Zone Info for Zone 4a

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 Zone 4a

You may be interested in your other planting guides for Zone 4a.