When can I plant Calliopsis in Zone 4a

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

You can figure out when you can plant calliopsis in Zone 4a by using the USDA zone info.


Planting Calendar for Calliopsis

Frost tolerance for calliopsis: Not tolerant of frost.
When you should plant them: After all chance of frost has passed.

Since calliopsis are not cold tolerant it's important 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 Zone 4a is May. However, you really should wait until June 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. You probably don't want to wait any later than that or else your calliopsis may not have a chance to fully mature. If you are starting your calliopsis indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Zone 4a. We can expect an average low temperature of -30°F in the coldest months of winter.

Since the USDA zone info for Zone 4a is an average our actual date of last frost will vary from year to year. Since half of the time in Zone 4a we get surprised by a frost after May 15 be ready to protect your calliopsis in the event of 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 our other planting guides for Zone 4a.