One of the first steps you take when you are figuring out 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 Boston you can figure out when you can plant pentas by looking at the USDA zone info.

Planting Calendar for Pentas

Frost tolerance for pentas:	Not tolerant of frost.
When to plant:	After the last frost has passed.

You should not plant pentas until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant pentas 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 pentas and expect a good harvest is probably August. Any later than that and your pentas may not have a chance to really do well. You can get started a little bit earlier by starting your pentas indoors.

Last Frost Date

On average the last frost is on April 15 in Boston. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for Boston is not always accurate the actual date of last frost is different every year. Half of the time in Boston it frosts late in the year after April 15 so make sure that you are prepared to cover your pentas in the event of 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.