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

One way of getting a good idea when it's the best time to plant penstemon is to examine the USDA zone info for Robbins.

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 means 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 Robbins 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. You can get started a few weeks earlier by starting your penstemon indoors.

Last Frost Date

In Robbins the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

It's important to remember that USDA zone info for Robbins is just an average and the actual date of last frost is different every year. Half of the time in Robbins there is a last frost after April 15 so always be ready to protect your penstemon in the event of a surprise late frost.

USDA Zone Info for Robbins

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Robbins

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