The USDA Zone info is a great tool for gardeners to help us estimate 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.

By checking out the USDA zone info for Sulphur you will 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.

Since lithospermum require warm weather you have to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant lithospermum in Sulphur 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. If you wait any later than that and 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 couple of weeks earlier.

Last Frost Date

In Sulphur the average date of last frost happens on February 15. You can expect an average low temperature of 20°F in the coldest months of winter.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Sulphur and it can change quite a bit from year to year. Since half of the time in Sulphur there is a last frost after February 15 be ready to protect your lithospermum if you have a surprise late frost.

USDA Zone Info for Sulphur

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Sulphur

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