One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of figuring out when you can plant penstemon is to examine the USDA zone info for Storm Lake.

Planting Calendar for Penstemon

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

Since penstemon are moderately cold tolerant you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant penstemon in Storm Lake 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. If you wait any later than that and your penstemon may not have a chance to really do well. 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 Storm Lake. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Storm Lake is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Storm Lake it frosts late in the year after April 15 so make sure that you are ready to protect your penstemon if you have a surprise late frost.

USDA Zone Info for Storm Lake

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Storm Lake

You may be interested in your other planting guides for Storm Lake.