Garden raised beds can help you grow better, tastier, and bigger vegetables. Raised beds filled with rich soil and organic amendments will warm faster in spring for an earlier start and an earlier harvest.
Use raised bed when the soil is poor—heavy clay or too loose sandy soil. Raised beds of rich, organic soil will be quick draining and full of plant nutrients.
Raised beds also can save you water and fertilizer and time. Your watering, feeding, and weeding efforts will be concentrated on the raised bed—commonly no more than 4 feet wide, and not on the surrounding unproductive ground.
Here’s how to build a garden raised bed:
1. A raised bed can as simple as a raised mound of soil. Choose the location for your planting bed and then from either side shovel surface soil to your intended growing bed. Add aged compost, planting mix, or store-bought top soil across the top of your raised mound and turn into the native soil. A raised mound should be at least 4 inches high; ten inches is better and will warm faster in spring as the sun shines on the side and top of the mound. A bed 4 feet wide will be easily accessible from either side; don’t make your raised wider than arm’s length so it is easily worked without stepping in to it. Make your raised bed just long enough to get from one side to the other.
2. Build a raised bed with timbers, planks, bricks, cement blocks, recycled concrete or wattles (landscape fabric filled with straw). Cedar or pine are the best choices for raised beds made from boards or planks; pine will last three to five years and cedar twice as long or more. Choose boards an inch or more thick and 8 inches or more wide and use posts or stakes to square off the bed at the ends. Be sure to select a flat site or rake it flat before you assemble the frame. If you live in gopher or burrowing pest country, line the bottom of the bed with hardware cloth. Once the bed is in place, fill it with aged compost and planting mix. Now you are ready to plant.
3. From one season to the next, add aged compost to your raised bed to keep it fresh and nutrient rich. You can add washed sand to beds in which you plan to plant carrots and root crops; a bit of sand will make the bed loose and friable. Raised beds can dry more quickly in hot weather—since the sides are exposed to the sun, so be sure to monitor the moisture in the soil by simply thrusting your finger into the soil every day or so to make sure it is moist, but not wet, a couple of inches below the surface.