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

It's possible to estimate when you can plant lithospermum by using the USDA zone info for Devils Lake.

Planting Calendar for Lithospermum

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

You can not plant lithospermum until after the last frost has passed because they require warm weather.

The earliest that you can plant lithospermum in Devils Lake 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 fully mature. You can get started a few weeks earlier by starting your lithospermum indoors.

Last Frost Date

In Devils Lake the average date of last frost happens on May 15. It might get as low as -30°F during the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Devils Lake and it changes from year to year. Half of the time in Devils Lake you get a frost after May 15 so be sure to be ready to protect your lithospermum if you have one of those late frosts.

USDA Zone Info for Devils Lake

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Devils Lake

You may be interested in your other planting guides for Devils Lake.