If you’re like most gardeners, you think of as structures enclosed and raised above the ground by some sort of frame. But raised beds with no walls also exist. In fact, they’re the most common way to build raised beds on a large scale, and they’re popular on small vegetable farms. These mounded raised beds are also great for home gardens.
Advantages of Growing in Unframed Raised Beds
Unframed raised beds offer most of the same advantages as framed raised beds. These include improved drainage, a deeper volume of loosened soil for plant roots to explore, and a raised growing surface that is easier to reach without kneeling. also warms up earlier in spring.
An additional advantage of unframed raised beds is that you can install them with significantly less expense and effort, which is especially important if you’re gardening on a large scale. You will also avoid the potential toxicity associated with some framing materials.
Potential Disadvantages of Growing in Unframed Raised Beds
Raised beds with no walls don’t last as long as those with walls, however. If left untended, they will eventually erode and sink back to the level of the surrounding soil. That being said, you can simply build them back up every year or two, and this presents an opportunity to work additional into the soil.
Mounded raised beds also take up more space than framed raised beds that provide an equivalent growing space. That’s because you need to account for the inclines at the margins of the bed. However, the lack of walls may allow