Double digging is a method for enhancing the structure of your garden’s soil. Soils that do not drain well will cause harm and virtually kill the biology that naturally enhances soil structure, as well as wasting money and time trying to grow a viable crop.
Even though double digging method is a time-consuming and labor-intensive method of improving soil structure, it has numerous advantages that can be long-lasting if properly managed. All you need is a garden spade or shovel, a tarp or wheelbarrow to cover the area you will be piling the dug soil on, organic soil amendments of your choosing, and the determination to complete this task.
To begin this process, sketch out the area you want to change. Start digging a trench at one end of the bed that is a comfortable width for you to work the length or width of the flower bed to extract the top layer of soil to a depth of one garden spade or shovel deep, and pile the excavated soil as you want, on the grass, in a wheelbarrow, or on a tarp to set aside for reuse.
Now, with your spade or shovel, loosen the subsoil layer under the soil you just removed by pressing it into the ground and working back and forth, just loosening it, not removing it. If the subsoil has been loosened, apply your preferred organic soil modification, such as compost, and gently work it in.
After you have double digging method for your entire garden bed, the soil should be several inches higher than the existing grade around it. If you do this in the fall, it will give the bedtime to settle out before you plant; if you do this in the spring and want to plant the garden bed once it is done. Water it thoroughly to allow it to settle, and then let nature take over by allowing natural biology, organisms, and microorganisms to work hard for you to improve the soil structure. All you have to do is feed the soil, and nature will take care of the rest.