The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By looking at the USDA zone info for Attleboro you should be able to estimate when it's the best time to plant penstemon.

Planting Calendar for Penstemon

Frost tolerance for penstemon:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant penstemon just a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant penstemon in Attleboro is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant penstemon and expect a good harvest is probably September. Any later than that and your penstemon may not have a chance to fully mature. Starting your penstemon indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Attleboro the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -5°F.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Attleboro and it will vary from year to year. Half of the time in Attleboro you get a frost after April 15 so make sure that you are ready to cover your penstemon if you have a late frost.

USDA Zone Info for Attleboro

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 Attleboro

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