One of the best tools that you have as gardeners to help us figure out 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.

A common way of determining when it's a good idea to plant lithospermum is to refer to the USDA zone info for Williamsport.

Planting Calendar for Lithospermum

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

It's not a good idea to plant lithospermum until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant lithospermum in Williamsport 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 really do well. Starting your lithospermum indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

Always keep in mind that USDA zone info for Williamsport is an average and the actual date of last frost will vary from year to year. Since half of the time in Williamsport last frost occurs after April 15 be ready to protect your lithospermum if you have a surprise late frost.

USDA Zone Info for Williamsport

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 Williamsport

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