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.

The USDA zone info for Zone 4a can be reviewed to estimate when it's the best time to plant corn salad.

Planting Calendar for Corn salad

Frost tolerance for corn salad:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

You really shouldn't plant corn salad until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant corn salad in Zone 4a is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant corn salad and expect a good harvest is probably August. If you wait any later than that and your corn salad may not have a chance to really do well. You can get started a little bit earlier by starting your corn salad indoors.

Last Frost Date

In Zone 4a the average date of last frost happens on May 15. In the coldest months of winter you can expect an average low temperature of -30°F.

Since the USDA zone info for Zone 4a is an average the actual date of last frost changes from year to year. Since half of the time in Zone 4a you get surprised by a frost after May 15 be ready to protect your corn salad if you have a late frost.

USDA Zone Info for Zone 4a

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Zone 4a

You may be interested in your other planting guides for Zone 4a.