When to Plant Peonies in Washington, IL

Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant peonies in Washington can be figured out 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.

Peonies are barely cold tolerant which tells us that you can plant them slightly earlier than other plants that might not handle the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant peonies
Possibly ok, but a risky time to plant peonies
Probably not a good time to plant peonies

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. You probably don't want to wait any later than that or else your peonies may not have a chance to really do well. Starting your peonies indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Washington. It might get as low as -15°F during the coldest months of winter.

It's important to remember that USDA zone info for Washington is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Washington there is a last frost after April 15 so be sure to be ready to protect your peonies if you have one of those late frosts.

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.