One of the best tools that you have as gardeners to help us estimate 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.

The first chance to plant iberis in River Grove can be figured out by using 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 tend to make it in a little bit of cold which tells us that you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant iberis in River Grove 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 couple of weeks earlier by starting your iberis indoors.

Last Frost Date

On average the last frost is on April 15 in River Grove. You can expect an average low temperature of -15°F in the coldest months of winter.

Always keep in mind that USDA zone info for River Grove is just an average and the actual date of last frost is different every year. Half of the time in River Grove you get surprised by a frost after April 15 so make sure that you are prepared to protect your iberis if you have a surprise late frost.

USDA Zone Info for River Grove

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 River Grove

You may be interested in your other planting guides for River Grove.