One of the first steps you take when you are determining your gardening schedule is find your 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.

By using the USDA zone info for Prospect Heights it's possible to figure out when it's possible to plant larkspur.

Planting Calendar for Larkspur

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

Larkspur do well in cold which means that you can start planting them much earlier than other plants that might not handle the cold.

The earliest that you can plant larkspur 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 larkspur and expect a good harvest is probably September. Any later than that and your larkspur may not have a chance to grow to maturity. If you are starting your larkspur indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Prospect Heights is not always accurate the actual date of last frost is different every year. Half of the time in Prospect Heights it frosts late in the year after April 15 so make sure that you are prepared to protect your larkspur if you have a surprise 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.