When to Plant Calliopsis in Washington, IL

The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant calliopsis in Washington can be figured out by using the USDA zone info.


Planting Calendar for Calliopsis

Frost tolerance for calliopsis: Not tolerant of frost.
When to plant: After the last frost when the weather gets warmer.

Since calliopsis are not cold tolerant it is necessary to wait until after the last frost before you can plant them.

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

The earliest that you can plant calliopsis in Washington 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 calliopsis and expect a good harvest is probably August. If you wait any later than that and your calliopsis may not have a chance to really do well. You can get started a little bit earlier by starting your calliopsis indoors.

Last Frost Date

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

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Washington and it is different every year. Since half of the time in Washington you get surprised by a frost after April 15 be ready to protect your calliopsis in the event of 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.