One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for Peoria Heights you should be able to estimate when it's the best time to plant lithospermum.

Planting Calendar for Lithospermum

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

It's probably a bad idea to plant lithospermum until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant lithospermum in Peoria Heights 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 lithospermum and expect a good harvest is probably August. Any later than that and your lithospermum may not have a chance to grow to maturity. Starting your lithospermum indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Peoria 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.

Just be sure to remember that USDA zone info for Peoria Heights is just an average and the actual date of last frost changes from year to year. Since half of the time in Peoria Heights last frost occurs after April 15 be ready to cover your lithospermum in the event of a surprise late frost.

USDA Zone Info for Peoria 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 Peoria Heights

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