One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant lithospermum in Broken Arrow can be estimated by referring to the USDA zone info.

Planting Calendar for Lithospermum

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

Since lithospermum do not do well in cold weather you really should wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant lithospermum in Broken Arrow 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. You probably don't want to wait any later than that or else 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 Broken Arrow the average date of last frost happens on April 15. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Broken Arrow is just an average the actual date of last frost will vary from year to year. Half of the time in Broken Arrow there is a last frost after April 15 so make sure that you are prepared to cover your lithospermum in the event of one of those late frosts.

USDA Zone Info for Broken Arrow

Here is the info for USDA Zone 7a.

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

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Broken Arrow

You may be interested in your other planting guides for Broken Arrow.