One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can determine when it's the best time to plant iberis in Willowbrook by reviewing 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.

You can plant iberis a little 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 iberis in Willowbrook 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 fully mature. You can get started a little bit earlier by starting your iberis indoors.

Last Frost Date

The average date of last frost is April 15 in Willowbrook. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Willowbrook may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Willowbrook last frost occurs after April 15 so make sure that you are ready to protect your iberis if you have a late frost.

USDA Zone Info for Willowbrook

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Willowbrook

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