The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when it's the best time to plant iberis in Zone 3a by referring to 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 do well in moderate cold.

The earliest that you can plant iberis in Zone 3a 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. If you wait any later than that and your iberis may not have a chance to fully mature. If you are starting your iberis indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Zone 3a the average date of last frost happens on May 15. You can expect an average low temperature of -40°F in the coldest months of winter.

It's important to remember that USDA zone info for Zone 3a is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Zone 3a last frost occurs after May 15 be ready to cover your iberis in the event of one of those late frosts.

USDA Zone Info for Zone 3a

Here is the info for USDA Zone 3a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-40°F
Highest Expected Low	-35°F

This means that on a really cold year, the coldest it will get is -40°F. On most years you should be prepared to experience lows near -35°F.

Plants to Grow in Zone 3a

You may be interested in your other planting guides for Zone 3a.