One of the first steps you take when you are making a decision about 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.

The first chance to plant calliopsis in Altoona should be estimated by referring to the USDA zone info.

Planting Calendar for Calliopsis

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

You can not plant calliopsis until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant calliopsis in Altoona 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. Any later than that and your calliopsis may not have a chance to really do well. You can get started a few weeks earlier by starting your calliopsis indoors.

Last Frost Date

In Altoona the average date of last frost happens on May 15. You can expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Altoona is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Altoona you get surprised by a frost after May 15 so be sure to be ready to cover your calliopsis in the event of one of those late frosts.

USDA Zone Info for Altoona

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Altoona

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