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

A way of making a decision about when it's possible to plant hardy hibiscus is to check out the USDA zone info for Detroit.

Planting Calendar for Hardy Hibiscus

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

Hardy Hibiscus are very cold tolerant which means that you can plant them a quite a bit earlier than other frost tender plants.

The earliest that you can plant hardy hibiscus in Detroit 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 hardy hibiscus and expect a good harvest is probably September. You probably don't want to wait any later than that or else your hardy hibiscus may not have a chance to really do well. You can get started a few weeks earlier by starting your hardy hibiscus indoors.

Last Frost Date

In Detroit the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -5°F.

Since the USDA zone info for Detroit is just an average the actual date of last frost changes from year to year. Since half of the time in Detroit there is a last frost after April 15 be ready to cover your hardy hibiscus if you have one of those late frosts.

USDA Zone Info for Detroit

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Detroit

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