Summer is a great time to try something new. How about gardening? No idea where to begin? Not enough space? Even the staunchest urbanites can be successful harvesters using raised garden beds. In fact, the most successful gardeners use raised beds to avoid many of the typical gardening challenges. It’s easy…whether you’re interning at the Botanic Gardens, or you’ve never picked up a shovel.
If you are still skeptical that this project is for you, consider how much you will enjoy the output. Have you ever tasted a home-grown tomato? You won’t go back after you have. A raised garden bed is an easy way to grow your favorite foods in a controlled space, and with minimal effort. The structure itself has four “walls,” which will contain your dirt, and eliminate erosion. Drainage will be built into the walls. Good sun exposure will not only warm your bed, but allow you to diversify your crop, and even extend the growing season. Plants are closely spaced, which makes watering more efficient, and allows for a more abundant crop. The tight spacing and the raised soil level mean less back-breaking effort in planting and harvesting. We’re talking high yield/low effort. This is your kind of farming! It’s practically fool-proof.
First, the dirt. You need nutrient-rich soil, not just the stuff you shoveled up from the side of your house. We’re talking custom-blended dirt. Compost will be an important ingredient in your soil, and in our next blog, we will teach you how to “make” compost. But, for now, we’ll concentrate on the structure itself.
The most successful – and attractive – raised beds are bottomless frames set into a shallow trench. The sides of your bed can be almost any durable material, like rock, bricks, or concrete. As long as there is capacity and drainage, most materials will work. But, the most common building material for raised beds is lumber. If you are planning to grow food in your garden, we highly recommend staying away from wood preserved with toxins. Use naturally, rot-resistant cedar or redwood. If you use pressure treated wood, or wood infused with alkaline copper quaternary, consider lining your bed with landscape fabric to prevent soil contact. The fabric is air and water permeable, and safe for edibles. Whatever type of wood you select, put the bed together with galvanized, or stainless screws and bolts.
Carefully consider where to plant your bed. Location is key, and should depend on what you intend to plant, the quantity, and whether there is enough surrounding space for you to properly maintain the bed. For example, a 3 x 6 foot bed is ample space for tall plants, like tomatoes, but narrow enough for you to move on either side of it. You will want your bed to be between one-and-two feet tall. That requires a manageable amount of dirt; any higher, and there’s really just too much dirt. It’s sloppy and unsightly. Try to find a flat area for this project. This will spare you some of that toil we were talking about earlier. Take advantage of the best sunlight; a north-south orientation is a good option, if you have it. Try to avoid areas shaded by a house, for example, or beneath trees. We recommend leaving around 18 inches on either side of your bed so you can walk, and close to two feet if you anticipate needing to move a wheel barrow or lawnmower past your bed.
Again, the kind of dirt you use in your raised bed is very important. Try to use a peat moss, compost, or soil mix. Level your soil, and then plant in straight rows. If you’re really feeling ambitious, you might like to plant more than one bed, allowing you to rotate crops, and adjust the irrigation needs of different plants. Perhaps that’s something to aspire to. No rush.
Once you have mapped your location and determined your dimensions, it’s time to prepare your site. Get your boots, gloves, and grab a shovel. The first thing you might need to do is remove any turf of weeds. Next, outline your site with string, and begin digging vertical strokes along your string outline. You are really only digging deep enough to bury your first layer of lumber half-way. This is the time to consider your drainage. You might want to add a layer of gravel, or even landscape fabric covered with gravel, to improve water flow. Gravel will eliminate a “bathtub” effect, and probably keep your excavation site a lot cleaner. Landscape fabric also curtails weed growth.