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

It's possible to estimate when to plant penstemon by reviewing the USDA zone info for Laurel.

Planting Calendar for Penstemon

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

Since penstemon are one of those plants that can tolerate a little bit of cold weather you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant penstemon in Laurel is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant penstemon and expect a good harvest is probably August. 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 few weeks earlier by starting your penstemon indoors.

Last Frost Date

The average date of last frost is May 15 in Laurel. You should expect an average low temperature of -25°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Laurel and it can change quite a bit from year to year. Half of the time in Laurel there is a last frost after May 15 so make sure that you are ready to cover your penstemon if you have a late frost.

USDA Zone Info for Laurel

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Laurel

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