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

You will be able to figure out when it's possible to plant tropical hibiscus by reviewing the USDA zone info for River Grove.

Planting Calendar for Tropical Hibiscus

Frost tolerance for tropical hibiscus:	Not tolerant of frost.
When to plant:	After the last frost.

It's a bad idea to plant tropical hibiscus until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant tropical hibiscus in River Grove 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 tropical hibiscus and expect a good harvest is probably August. You probably don't want to wait any later than that or else your tropical hibiscus may not have a chance to fully mature. If you are starting your tropical hibiscus indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for River Grove is just an average the actual date of last frost will vary from year to year. Half of the time in River Grove it frosts late in the year after April 15 so make sure that you are prepared to cover your tropical hibiscus in the event of one of those late frosts.

USDA Zone Info for River Grove

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in River Grove

You may be interested in your other planting guides for River Grove.