One of the first steps you take when you are estimating 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.

A way of figuring out when it's the best time to plant penstemon is to refer to the USDA zone info for Sweetwater.

Planting Calendar for Penstemon

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

Since penstemon do well in moderate cold you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant penstemon in Sweetwater 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 couple of weeks earlier.

Last Frost Date

In Sweetwater the average date of last frost happens on April 15. You should expect an average low temperature of 0°F in the coldest months of winter.

Keep in mind that USDA zone info for Sweetwater is not always accurate and the actual date of last frost is different every year. Since half of the time in Sweetwater last frost occurs after April 15 be ready to protect your penstemon in the event of one of those late frosts.

USDA Zone Info for Sweetwater

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 Sweetwater

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