Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of making a decision about when to plant lithospermum is to examine the USDA zone info for Carnegie.

Planting Calendar for Lithospermum

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

It's a bad idea to plant lithospermum until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant lithospermum in Carnegie 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 couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Carnegie. In the coldest months of winter you can expect an average low temperature of -5°F.

Since the USDA zone info for Carnegie is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Carnegie last frost occurs after April 15 be ready to cover your lithospermum in the event of one of those late frosts.

USDA Zone Info for Carnegie

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°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 0°F.

Plants to Grow in Carnegie

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