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.

In Herrin you can estimate when it's possible to plant evolvulus by using the USDA zone info.

Planting Calendar for Evolvulus

Frost tolerance for evolvulus:	Not tolerant of frost.
When to plant:	After the last frost.

Evolvulus do not do well in cold weather which means that you have to wait until it warms up after all chance of frost has passed before you can plant them.

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

The last month that you can plant evolvulus and expect a good harvest is probably August. Any later than that and your evolvulus may not have a chance to fully mature. If you are starting your evolvulus indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Herrin. It might get as low as -5°F during the coldest months of winter.

Keep in mind that USDA zone info for Herrin is just an average and the actual date of last frost is different every year. Half of the time in Herrin it frosts late in the year after April 15 so always be ready to cover your evolvulus if you have one of those late frosts.

USDA Zone Info for Herrin

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Herrin

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