One of the first steps you take when you are determining 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 Holly you can figure out when it's possible to plant penstemon by reviewing the USDA zone info.

Planting Calendar for Penstemon

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

Penstemon can survive in mild cold which tells us that you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant penstemon in Holly 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 couple of weeks earlier.

Last Frost Date

In Holly the average date of last frost happens on April 15. You can expect an average low temperature of -10°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Holly and it changes from year to year. Half of the time in Holly it frosts late in the year after April 15 so make sure that you are prepared to protect your penstemon if you have a surprise late frost.

USDA Zone Info for Holly

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Holly

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