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.

The first chance to plant penstemon in Greenbelt should be determined by referring to 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 can survive in mild cold which tells us that you can plant them a little bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant penstemon in Greenbelt 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. If you wait any later than that and your penstemon may not have a chance to grow to maturity. Starting your penstemon indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Greenbelt. In the coldest months of winter you can expect an average low temperature of 0°F.

Since the USDA zone info for Greenbelt is just an average the actual date of last frost will vary from year to year. Since half of the time in Greenbelt it frosts late in the year after April 15 be ready to cover your penstemon if you have a late frost.

USDA Zone Info for Greenbelt

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 Greenbelt

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