One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. 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 determine when it's possible to plant heliotrope by using the USDA zone info for Gurnee.

Planting Calendar for Heliotrope

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

Heliotrope are not cold tolerant which tells us that it is necessary to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant heliotrope in Gurnee 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. Any later than that and your heliotrope may not have a chance to grow to maturity. Starting your heliotrope indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Gurnee. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Gurnee is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Gurnee you get a frost after April 15 so just be sure to be ready to cover your heliotrope if you have one of those late frosts.

USDA Zone Info for Gurnee

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 Gurnee

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