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.

By reviewing the USDA zone info for Bartlett it's possible to estimate when it's the best time to plant penstemon.

Planting Calendar for Penstemon

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

Penstemon tend to make it in moderate cold which tells us that you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant penstemon in Bartlett 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. You can get started a couple of weeks earlier by starting your penstemon indoors.

Last Frost Date

The average date of last frost is April 15 in Bartlett. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Bartlett may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in Bartlett you get surprised by a frost after April 15 be ready to protect your penstemon in the event of one of those late frosts.

USDA Zone Info for Bartlett

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 Bartlett

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