Before planting it is a good idea to find your USDA Zone info to estimate 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 Harrison you can determine when it's a good idea 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.

You can plant penstemon a little bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant penstemon in Harrison 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 really do well. Starting your penstemon indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Harrison the average date of last frost happens on April 15. It might get as low as 0°F during the coldest months of winter.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Harrison and it changes from year to year. Since half of the time in Harrison you get surprised by a frost after April 15 be ready to protect your penstemon in the event of a late frost.

USDA Zone Info for Harrison

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Harrison

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