For some, the idea of a raised bed planter is pretty simple – just some wood that will hold the soil in place. The overall design is functional, but there’s no desire to have anything fancy. And, more than anything, durability and longevity are the goals.
One of the decisions that a garden-builder must make early in the consideration of design is the choice of materials. While Pine is the least expensive, it comes with the likelihood of warping. It’s a combination of the quality of the material, as well as the fact that most wood that is available at your big box stores is young wood that is subject to twisting and turning just because it isn’t truly mature.
Cedar is a better material, but the cost is significantly higher. It’s also a generally rough material, which means that it’s going to be something you will feel with your hands, arms, and legs as you work your garden. Cedar is generally not smooth, and while you may not get actual splinters, it may feel like you are going to.
One way to mitigate these concerns is to consider the beefier 4×6 timbers that are pine, but will not warp in the same way thinner boards will. They will also create corners on their own without the need for vertical posts. The boards can overlap, and you can stack them to create taller boxes with ease.
In addition, when you use 2×10 or 2×12 boards, you have to keep the runs between vertical posts to about 6 feet of less. The warpage can make the box look twisted, and sometimes the weight of the soil can lead to blowouts of the boards entirely – particularly if it is a double-high design.
Using 4×6 timbers alleviates that concern, and allows you to have much longer boxes that can appear continuous with overlapping boards. The design shown here is 24 feet long, and only requires two lengths of board to achieve that continuity. The 6″ height of each board, double-stacked, gives you a 12″ planter, which is suitable for most above-ground crops.
If you have space where you are looking for the simplicity of rectangular planters, and simply want to have a design that will last for years and year, using 4×6 timbers is way to get there quickly and with minimal effort.
The designs above were installed by High Altitude Landscape in Fort Collins, CO.