A favorite with rabbits, carrots are a root vegetable that can require special care. The main challenge for carrots is soil preparation. According to Jonathan Mueller, landscape architect with Landmark, carrots don't do well without at least 6 inches (15.24 centimeters) of soil that's well tilled and loosened. You also want to be careful about the type of soil that you choose to use. "If there are any pebbles or anything in the soil, the roots will grow around those pebbles so you'll get very misshapen roots," says Timothy Coolong, Ph.D., extension vegetable specialist for the University of Kentucky.
The type of soil is also crucial. Carrots are very difficult to grow in clay soils. Mineral soils work well, but humus is a better bet. If you don't have the right kind of soil in your yard, try growing carrots in raised beds. This will allow you to have a good deal of oversight related to the soil composition and ground moisture.