Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Mound you can determine when it's the best time to plant penstemon by looking at 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 do well in moderate cold which means that you can start planting them earlier than more sensitive plants.

The earliest that you can plant penstemon in Mound 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. If you wait 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 little bit earlier.

Last Frost Date

In Mound the average date of last frost happens on May 15. You can expect an average low temperature of -25°F in the coldest months of winter.

Just be sure to remember 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 Mound and it changes from year to year. Half of the time in Mound it frosts late in the year after May 15 so make sure that you are prepared to protect your penstemon in the event of a surprise late frost.

USDA Zone Info for Mound

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 Mound

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