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

A common way of determining when to plant iberis is to examine the USDA zone info for Red Oak.

Planting Calendar for Iberis

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

Iberis do ok in mild cold which tells us that you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant iberis in Red Oak 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. Any later than that and 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 few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Red Oak. In the coldest months of winter you can expect an average low temperature of -20°F.

Since the USDA zone info for Red Oak is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Red Oak last frost occurs after April 15 so just be sure to be ready to protect your iberis in the event of one of those late frosts.

USDA Zone Info for Red Oak

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Red Oak

You may be interested in your other planting guides for Red Oak.