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.

The USDA zone info for Manville should be used to estimate when it's the best time 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 do ok in mild cold which means that you can plant them just a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant penstemon in Manville 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. You can get started a little bit earlier by starting your penstemon indoors.

Last Frost Date

The average date of last frost is April 15 in Manville. In the coldest months of winter you should expect an average low temperature of -5°F.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Manville and it is different every year. Half of the time in Manville it frosts late in the year after April 15 so always be ready to cover your penstemon in the event of one of those late frosts.

USDA Zone Info for Manville

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Manville

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