The USDA Zone info is a great tool for gardeners to help us estimate 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.

You can figure out when you can plant heliotrope in Decorah by reviewing the USDA zone info.

Planting Calendar for Heliotrope

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

Heliotrope do not do well in cold weather which means that you have to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant heliotrope in Decorah 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 heliotrope and expect a good harvest is probably August. You probably don't want to wait any later than that or else your heliotrope may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your heliotrope indoors.

Last Frost Date

In Decorah the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Decorah and it changes from year to year. Half of the time in Decorah you get a frost after May 15 so make sure that you are prepared to cover your heliotrope if you have a surprise late frost.

USDA Zone Info for Decorah

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 Decorah

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