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.

You can determine when to plant iberis in Madison 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.

Iberis tend to make it in moderate cold which means that you can plant them just a bit earlier in the year than other frost tender plants.

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

The last month that you can plant iberis and expect a good harvest is probably August. You probably don't want to wait any later than that or else your iberis may not have a chance to grow to maturity. If you are starting your iberis indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Madison the average date of last frost happens on May 15. In the coldest months of winter you should expect an average low temperature of -25°F.

Always keep in mind that USDA zone info for Madison is not always accurate and the actual date of last frost is different every year. Half of the time in Madison it frosts late in the year after May 15 so always be ready to cover your iberis in the event of one of those late frosts.

USDA Zone Info for Madison

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Madison

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