1. Plants in raised beds get more sun and air circulation and they can make better use of water. You often can plant earlier and harvest later, because raised beds warm up early in the spring and stay warm later in the fall. 2. Raised beds also make ideal places to grow plants that can be invasive in a regular garden - such as mints and horseradish. But ease and convenience is the benefit many gardeners appreciate the most. If you get a bad back and sore knees every year from gardening, a raised bed may put an end to those aches and pains.