The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Columbus can be looked at to estimate when it's possible to plant calliopsis.

Planting Calendar for Calliopsis

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

You should not plant calliopsis until after the last frost has passed because they require warm weather.

The earliest that you can plant calliopsis in Columbus 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. Any later than that and your calliopsis may not have a chance to really do well. Starting your calliopsis indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Columbus the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -20°F.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Columbus and it can change quite a bit from year to year. Since half of the time in Columbus you get surprised by a frost after April 15 be ready to cover your calliopsis if you have one of those late frosts.

USDA Zone Info for Columbus

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Columbus

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