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.

You should be able to estimate when it's possible to plant penstemon by looking at the USDA zone info for Dickinson.

Planting Calendar for Penstemon

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

Penstemon tend to make it in some cold which tells us that you can plant them just a bit earlier in the year than other frost tender plants.

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

The last month that you can plant penstemon and expect a good harvest is probably October. Any later than that and your penstemon may not have a chance to grow to maturity. If you are starting your penstemon indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost has passed is on February 15 in Dickinson. In the coldest months of winter you should expect an average low temperature of 20°F.

Just be sure to remember that USDA zone info for Dickinson is just an average and the actual date of last frost changes from year to year. Since half of the time in Dickinson there is a last frost after February 15 be ready to protect your penstemon if you have a late frost.

USDA Zone Info for Dickinson

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Dickinson

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