One of the best tools that you have as gardeners to help us determine 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.

In Plano you can figure out when it's the best time to plant penstemon by checking out 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 other frost tender plants.

The earliest that you can plant penstemon in Plano 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 fully mature. If you are starting your penstemon indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Plano. In the coldest months of winter you can expect an average low temperature of 10°F.

Since the USDA zone info for Plano is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Plano you get a frost after March 15 be ready to protect your penstemon in the event of a late frost.

USDA Zone Info for Plano

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

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

Plants to Grow in Plano

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