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

By reviewing the USDA zone info for Marshalltown you should be able to determine when it's the best time to plant liatris.

Planting Calendar for Liatris

Frost tolerance for liatris:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since liatris are one of those plants that can tolerate quite a bit of cold weather you can plant them much earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant liatris in Marshalltown is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant liatris and expect a good harvest is probably September. Any later than that and your liatris may not have a chance to grow to maturity. If you are starting your liatris indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

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

Since the USDA zone info for Marshalltown is not always accurate the actual date of last frost can change quite a bit from year to year. Since half of the time in Marshalltown it frosts late in the year after April 15 be ready to cover your liatris if you have one of those late frosts.

USDA Zone Info for Marshalltown

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 Marshalltown

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