One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can estimate when it's possible to plant peonies in Washington by referring to 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.

You can plant peonies a bit earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant peonies in Washington 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 peonies and expect a good harvest is probably August. Any later than that and your peonies may not have a chance to really do well. You can get started a couple of weeks earlier by starting your peonies indoors.

Last Frost Date

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

Since the USDA zone info for Washington may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Washington you get surprised by a frost after April 15 so be sure to be ready to protect your peonies in the event of a surprise late frost.

USDA Zone Info for Washington

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Washington

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