One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can estimate when it's possible to plant penstemon in Middleton by using 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 tend to make it in moderate cold which tells us that 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 Middleton 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. Starting your penstemon indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Middleton 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 Middleton there is a last frost after April 15 so always be ready to protect your penstemon if you have one of those late frosts.

USDA Zone Info for Middleton

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 Middleton

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