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

The USDA zone info for Prospect Heights can be looked at to determine when you can plant lobelia.

Planting Calendar for Lobelia

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

Lobelia are one of those plants that can tolerate quite a bit of cold weather which means that you can start planting them much earlier than plants that are more sensitive to the cold.

The earliest that you can plant lobelia in Prospect Heights 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 lobelia and expect a good harvest is probably September. If you wait any later than that and your lobelia may not have a chance to really do well. If you are starting your lobelia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Keep in mind that USDA zone info for Prospect Heights is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Prospect Heights you get surprised by a frost after April 15 be ready to cover your lobelia in the event of a late frost.

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.