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

A common way of getting a good idea when to plant lithospermum is to refer to the USDA zone info for Airway Heights.

Planting Calendar for Lithospermum

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

Since lithospermum do not do well in cold weather you have to wait until after the last frost before you can plant them.

The earliest that you can plant lithospermum in Airway Heights 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. Any later than that and your lithospermum may not have a chance to really do well. Starting your lithospermum indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Airway Heights. In the coldest months of winter you should expect an average low temperature of -10°F.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Airway Heights and it changes from year to year. Half of the time in Airway Heights you get a frost after April 15 so make sure that you are prepared to cover your lithospermum if you have a surprise late frost.

USDA Zone Info for Airway Heights

Here is the info for USDA Zone 6a.

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

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

Plants to Grow in Airway Heights

You may be interested in your other planting guides for Airway Heights.