One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of getting a good idea when it's possible to plant penstemon is to examine the USDA zone info for Inverness.

Planting Calendar for Penstemon

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

Since penstemon do well in moderate cold you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant penstemon in Inverness is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant penstemon and expect a good harvest is probably October. 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 couple of weeks earlier.

Last Frost Date

In Inverness the average date of last frost happens on February 15. You can expect an average low temperature of 20°F in the coldest months of winter.

Always keep in mind that USDA zone info for Inverness is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Inverness you get a frost after February 15 be ready to cover your penstemon in the event of one of those late frosts.

USDA Zone Info for Inverness

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°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 25°F.

Plants to Grow in Inverness

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