One of the best tools that you have as gardeners to help us figure out 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.

In Indiana you can estimate when it's possible to plant hardy hibiscus by using the USDA zone info.

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 tend to make it in pretty solid cold which tells us that you can plant them quite a bit earlier in the year than other frost tender plants.

The earliest that you can plant hardy hibiscus in Indiana 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. Any later than that and your hardy hibiscus may not have a chance to grow to maturity. If you are starting your hardy hibiscus indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Indiana the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

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

USDA Zone Info for Indiana

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 Indiana

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