One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant heliotrope in Napoleon should be estimated by using the USDA zone info.

Planting Calendar for Heliotrope

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

Heliotrope are not cold tolerant which means that you really should 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 Napoleon 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 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 fully mature. Starting your heliotrope indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Napoleon the average date of last frost happens on April 15. You can expect an average low temperature of -10°F in the coldest months of winter.

Keep in mind that USDA zone info for Napoleon is an average and the actual date of last frost changes from year to year. Since half of the time in Napoleon you get a frost after April 15 be ready to protect your heliotrope in the event of one of those late frosts.

USDA Zone Info for Napoleon

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Napoleon

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