Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By looking at the USDA zone info for Seward you should be able to figure out when to plant lithospermum.

Planting Calendar for Lithospermum

Frost tolerance for lithospermum:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Lithospermum require warm weather which tells us that you need to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant lithospermum in Seward 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. You probably don't want to wait any later than that or else your lithospermum may not have a chance to grow to maturity. If you are starting your lithospermum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Just be sure to remember that USDA zone info for Seward is just an average and the actual date of last frost is different every year. Since half of the time in Seward you get a frost after April 15 be ready to cover your lithospermum if you have a surprise late frost.

USDA Zone Info for Seward

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 Seward

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