One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to figure out when you can plant penstemon by looking at the USDA zone info for Blytheville.

Planting Calendar for Penstemon

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

Penstemon are one of those plants that can tolerate a little bit of cold weather which means that you can start planting them earlier than other plants that might not handle the cold.

The earliest that you can plant penstemon in Blytheville 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 grow to maturity. You can get started a little bit earlier by starting your penstemon indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Blytheville. In the coldest months of winter you can expect an average low temperature of 5°F.

Keep in mind that USDA zone info for Blytheville may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Blytheville you get surprised by a frost after April 15 so always be ready to cover your penstemon in the event of a late frost.

USDA Zone Info for Blytheville

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Blytheville

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