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

It's a good idea to determine when it's possible to plant penstemon by looking at the USDA zone info for Troy.

Planting Calendar for Penstemon

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

Penstemon are moderately cold tolerant which means that you can plant them earlier than other plants that might not handle the cold.

The earliest that you can plant penstemon in Troy 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 grow to maturity. Starting your penstemon indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Troy the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Troy and it can change quite a bit from year to year. Half of the time in Troy there is a last frost after April 15 so just be sure to be ready to cover your penstemon in the event of a surprise late frost.

USDA Zone Info for Troy

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 Troy

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