One of the first steps you take when you are making a decision about 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.

A way of determining when you can plant penstemon is to look at the USDA zone info for Bristow.

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 plant them earlier than plants that are more sensitive to the cold.

The earliest that you can plant penstemon in Bristow 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 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

On average the last frost has passed is on April 15 in Bristow. You can expect an average low temperature of 0°F in the coldest months of winter.

Remember that USDA zone info for Bristow is not always accurate and the actual date of last frost is different every year. Since half of the time in Bristow it frosts late in the year after April 15 be ready to protect your penstemon if you have one of those late frosts.

USDA Zone Info for Bristow

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Bristow

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