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

By using the USDA zone info for Prospect Heights you should be able to figure out when you can plant regal geranium.

Planting Calendar for Regal Geranium

Frost tolerance for regal geranium:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant regal geranium slightly earlier in the year because they are barely cold tolerant.

The earliest that you can plant regal geranium in Prospect Heights is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant regal geranium and expect a good harvest is probably August. Any later than that and your regal geranium may not have a chance to fully mature. Starting your regal geranium indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

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

USDA Zone Info for Prospect Heights

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 Prospect Heights

You may be interested in your other planting guides for Prospect Heights.