One of the best tools that you have as gardeners to help us determine 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 Minneapolis can be reffered to in order to estimate when you can plant lithospermum.

Planting Calendar for Lithospermum

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

Lithospermum are not cold tolerant which tells us that it's necessary to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant lithospermum in Minneapolis is May. However, you really should wait until June 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. You probably don't want to wait any later than that or else your lithospermum may not have a chance to really do well. You can get started a few weeks earlier by starting your lithospermum indoors.

Last Frost Date

The average date of last frost is May 15 in Minneapolis. In the coldest months of winter you can expect an average low temperature of -25°F.

Remember that USDA zone info for Minneapolis is an average and the actual date of last frost is different every year. Since half of the time in Minneapolis there is a last frost after May 15 be ready to protect your lithospermum if you have a late frost.

USDA Zone Info for Minneapolis

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Minneapolis

You may be interested in your other planting guides for Minneapolis.