One of the first steps you take when you are determining 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.

One way of making a decision about when you can plant lithospermum is to look at the USDA zone info for Sun Prairie.

Planting Calendar for Lithospermum

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

You really shouldn't plant lithospermum until after the last frost when the weather gets warmer because they require warm weather.

The earliest that you can plant lithospermum in Sun Prairie 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. If you wait any later than that and your lithospermum may not have a chance to fully mature. If you are starting your lithospermum indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Sun Prairie. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Sun Prairie is not always accurate the actual date of last frost will vary from year to year. Half of the time in Sun Prairie you get surprised by a frost after April 15 so make sure that you are ready to protect your lithospermum if you have one of those late frosts.

USDA Zone Info for Sun Prairie

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Sun Prairie

You may be interested in your other planting guides for Sun Prairie.