Finally, spring has arrived. We’ve survived another Nebraska winter and have done every indoor chore on our “to-do” lists. Our gardening tools are ready; some seeds have already been started in our basement greenhouses. All we’re waiting on is the weather, specifically warmer air and soil temperatures, to launch our season. What else can we do while we wait? Well, now is a good time to build a raised planting bed.
The basic idea of a raised bed is that instead of battling against poor soil conditions, you build above ground, where you have absolute control over the soil texture and ingredients.
Growing in raised beds has many advantages. It can be easier on aging backs and knees, and optimal soil conditions inside a raised bed can easily be maintained. By relegating external areas to the compaction of walking and wheelbarrows, the contained soil stays aerated, thus draining better. Raised beds can be maintained by simply topping with compost or mulch. Another advantage to raised beds is that they extend a gardener's growing season because the walls collect early spring sun and warm up before native soil, giving plants and seeds a jump on the growing season.
There are some key considerations when selecting a site for a raised bed. A flat, level area works best for a raised bed. If there are specific plants you want to grow, make sure you’ve located your bed so it receives the correct amount of sunlight. Having a water source close at hand is important. A raised bed will dry out more quickly due to improved drainage and quality soil so you’ll want to minimize the distance you have to travel with a hose or other irrigation device.
Another important component in selecting the location of the bed is its size. The point of raised bed is to avoid soil compaction, i.e. all weight-bearing activity such as walking, kneeling, and wheelbarrow placement occurs outside the bed boundaries. By not stepping in the bed, soil remains light and fluffy and keeps your plant’s roots happy. If you will have room to work on either side of the bed, a four-foot width is ideal.
When prepping your site, you will want to remove the existing sod. There are two ways to do this. If you want to skip your workout for the day, grab a shovel and dig out the sod and loosen the soil with a shovel or garden fork to a depth of 8 – 12 inches. A less labor-intensive alternative is to lay down newspaper or landscape fabric, effectively smothering the sod.
Raised beds can be constructed from a variety of materials and are a matter of personal preference. Treated lumber should be avoided as it can leach hazardous chemicals. Cedar and redwood will resist rotting and are good alternatives as are stones, cinderblocks, and bricks. Once the frame has been constructed, fill it with a good mixture of quality topsoil, compost and rotted manure to a minimum depth of six inches. To ensure the plants’ roots have ample room to grow, a depth of 8 – 12 inches is ideal. Rake the soil mixture level and you are ready to plant.
Happily, raised bed gardens require very little maintenance. Each spring or fall, it's a good idea to top dress with fresh compost and manure, or if your bed only holds plants for part of the year, go ahead and dig the compost or manure into the top several inches of soil. As with any garden, mulching the top of the soil will help retain moisture and keep minimize weeds growth.
If you have raised beds as part of your landscape or if you build a raised bed this spring, send us a note and let us know about your experience. As always, we love to see pictures of your projects, so we hope you’ll send us those as well.
Rachael and Tobias