One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant salpiglossis in Boston can be determined by reviewing the USDA zone info.

Planting Calendar for Salpiglossis

Frost tolerance for salpiglossis:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

You really shouldn't plant salpiglossis until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant salpiglossis in Boston 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 salpiglossis and expect a good harvest is probably August. You probably don't want to wait any later than that or else your salpiglossis may not have a chance to grow to maturity. Starting your salpiglossis indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Boston. You should expect an average low temperature of -5°F in the coldest months of winter.

Remember that USDA zone info for Boston is not always accurate and the actual date of last frost changes from year to year. Half of the time in Boston there is a last frost after April 15 so be sure to be ready to cover your salpiglossis if you have a late frost.

USDA Zone Info for Boston

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 Boston

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