One of the first steps you take when you are estimating 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.

In Herrin you can determine when it's a good idea to plant iberis by checking out the USDA zone info.

Planting Calendar for Iberis

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

Iberis are moderately cold tolerant which tells us that you can plant them a little bit earlier than other frost tender plants.

The earliest that you can plant iberis in Herrin 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 iberis and expect a good harvest is probably September. If you wait any later than that and your iberis may not have a chance to really do well. You can get started a little bit earlier by starting your iberis indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Herrin. In the coldest months of winter you can expect an average low temperature of -5°F.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Herrin and it is different every year. Since half of the time in Herrin you get a frost after April 15 be ready to protect your iberis 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.