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.

The first chance to plant penstemon in Johnson City can be figured out by referring to 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 are moderately cold tolerant which tells us that you can get them planted earlier than plants that are more sensitive to the cold.

The earliest that you can plant penstemon in Johnson City 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. Any later than that and 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

On average the last frost is on April 15 in Johnson City. In the coldest months of winter you can expect an average low temperature of -15°F.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Johnson City and it will vary from year to year. Half of the time in Johnson City you get a frost after April 15 so make sure that you are prepared to protect your penstemon in the event of one of those late frosts.

USDA Zone Info for Johnson City

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Johnson City

You may be interested in your other planting guides for Johnson City.