Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By referring to the USDA zone info for Zone 4b it's possible to estimate when you can plant carrots.

Planting Calendar for Carrots

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

You can plant carrots a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant carrots in Zone 4b 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 carrots and expect a good harvest is probably August. You probably don't want to wait any later than that or else your carrots may not have a chance to really do well. If you are starting your carrots indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Zone 4b the average date of last frost happens on May 15. In the coldest months of winter you can expect an average low temperature of -25°F.

Keep in mind that USDA zone info for Zone 4b may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Zone 4b last frost occurs after May 15 be ready to protect your carrots in the event of one of those late frosts.

USDA Zone Info for Zone 4b

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 Zone 4b

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