One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. 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 Sulphur.

Planting Calendar for Lithospermum

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

Lithospermum require warm weather which means 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 Sulphur 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 fully mature. 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 Sulphur the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of 5°F.

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 it frosts late in the year after April 15 be ready to cover your lithospermum in the event of a surprise late frost.

USDA Zone Info for Sulphur

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Sulphur

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