The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant penstemon in Green Bay should be figured out by reviewing 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.

You can plant penstemon a little bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant penstemon in Green Bay 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. Starting your penstemon indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Green Bay. In the coldest months of winter you should expect an average low temperature of -20°F.

Since the USDA zone info for Green Bay may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Green Bay last frost occurs after April 15 so make sure that you are prepared to protect your penstemon in the event of a surprise late frost.

USDA Zone Info for Green Bay

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Green Bay

You may be interested in your other planting guides for Green Bay.