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 Mendota should be used to estimate 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.

Since penstemon are moderately cold tolerant you can plant them a little bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant penstemon in Mendota 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. 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 when the weather gets warmer is on April 15 in Mendota. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Mendota is not always accurate the actual date of last frost changes from year to year. Half of the time in Mendota it frosts late in the year after April 15 so just be sure to be ready to cover your penstemon if you have one of those late frosts.

USDA Zone Info for Mendota

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Mendota

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