Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Montpelier should be reviewed to determine when it's a good idea 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.

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

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

The last month that you can plant penstemon and expect a good harvest is probably August. You probably don't want to wait any later than that or else your penstemon may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your penstemon indoors.

Last Frost Date

On average the last frost has passed is on May 15 in Montpelier. In the coldest months of winter you should expect an average low temperature of -25°F.

Since the USDA zone info for Montpelier is not always accurate the actual date of last frost is different every year. Half of the time in Montpelier you get surprised by a frost after May 15 so make sure that you are prepared to protect your penstemon in the event of a late frost.

USDA Zone Info for Montpelier

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

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

Plants to Grow in Montpelier

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