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.

The best time to plant penstemon in Yankton can be figured out 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.

Penstemon do well in moderate cold which tells us that you can get them planted earlier than other frost tender plants.

The earliest that you can plant penstemon in Yankton 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. You probably don't want to wait any later than that or else your penstemon may not have a chance to grow to maturity. Starting your penstemon indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Yankton. In the coldest months of winter you should expect an average low temperature of -20°F.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Yankton and it changes from year to year. Since half of the time in Yankton you get surprised by a frost after April 15 be ready to protect your penstemon in the event of a surprise late frost.

USDA Zone Info for Yankton

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 Yankton

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