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 figuring out when it's possible to plant lithospermum is to consult the USDA zone info for Hackettstown.

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 are not cold tolerant you really should wait until after the last frost has passed before you can plant them.

The earliest that you can plant lithospermum in Hackettstown 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 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

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

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Hackettstown and it changes from year to year. Half of the time in Hackettstown you get surprised by a frost after April 15 so be sure to be ready to cover your lithospermum if you have one of those late frosts.

USDA Zone Info for Hackettstown

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 Hackettstown

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