The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can determine when you can plant penstemon in New Ulm by using 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.

You can plant penstemon a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant penstemon in New Ulm 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. 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 New Ulm the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Always keep in mind that USDA zone info for New Ulm is not always accurate and the actual date of last frost will vary from year to year. Half of the time in New Ulm you get a frost after May 15 so make sure that you are prepared to cover your penstemon if you have a late frost.

USDA Zone Info for New Ulm

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 New Ulm

You may be interested in your other planting guides for New Ulm.