One of the first steps you take when you are estimating 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.

In Somerville you can figure out when you can plant lithospermum by using the USDA zone info.

Planting Calendar for Lithospermum

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

It's a bad idea to plant lithospermum until after the last frost has passed because they require warm weather.

The earliest that you can plant lithospermum in Somerville 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 few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Somerville. You should expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for Somerville is an average the actual date of last frost changes from year to year. Half of the time in Somerville you get a frost after April 15 so make sure that you are ready to protect your lithospermum in the event of one of those late frosts.

USDA Zone Info for Somerville

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 Somerville

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