The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A common way of determining when it's a good idea to plant lithospermum is to examine the USDA zone info for Spring Valley.

Planting Calendar for Lithospermum

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

It's probably a bad idea to plant lithospermum until after the last frost because they require warm weather.

The earliest that you can plant lithospermum in Spring Valley 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 grow to maturity. You can get started a few weeks earlier by starting your lithospermum indoors.

Last Frost Date

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

Since the USDA zone info for Spring Valley is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Spring Valley last frost occurs after April 15 so just be sure to be ready to cover your lithospermum in the event of a late frost.

USDA Zone Info for Spring Valley

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 Spring Valley

You may be interested in your other planting guides for Spring Valley.