One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can determine when you can plant lithospermum in New Castle 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.

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

The earliest that you can plant lithospermum in New Castle 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 grow to maturity. 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 is on April 15 in New Castle. In the coldest months of winter you should expect an average low temperature of -15°F.

Remember that USDA zone info for New Castle is just an average and the actual date of last frost will vary from year to year. Half of the time in New Castle there is a last frost after April 15 so make sure that you are prepared to protect your lithospermum if you have a surprise late frost.

USDA Zone Info for New Castle

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in New Castle

You may be interested in your other planting guides for New Castle.