The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Winters can be reviewed to estimate when it's possible 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.

Since lithospermum are not cold tolerant you have to wait until after the last frost has passed before you can plant them.

The earliest that you can plant lithospermum in Winters is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant lithospermum and expect a good harvest is probably September. 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 little bit earlier by starting your lithospermum indoors.

Last Frost Date

The average date of last frost is February 15 in Winters. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Winters is not always accurate the actual date of last frost is different every year. Since half of the time in Winters you get surprised by a frost after February 15 be ready to protect your lithospermum in the event of one of those late frosts.

USDA Zone Info for Winters

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°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 30°F.

Plants to Grow in Winters

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