Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You should be able to estimate when it's the best time to plant lithospermum by checking out the USDA zone info for Imperial.

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 require warm weather it is necessary to wait until after the last frost before you can plant them.

The earliest that you can plant lithospermum in Imperial is February. However, you really should wait until March 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. Any later than that and 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

On average the last frost has passed is on January 31 in Imperial. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for Imperial may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Imperial it frosts late in the year after January 31 so just be sure to be ready to cover your lithospermum if you have a surprise late frost.

USDA Zone Info for Imperial

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°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 35°F.

Plants to Grow in Imperial

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