Thriving gardens aren't just for farmers with acres of land. With a raised bed, you can grow vegetables, fruits, flowers, and herbs in a fraction of the space. Raised beds are ideal if you have poor native soil, a short growing season, or struggle with pesky weeds. They're also kinder on your knees than ground-level garden, because you can maintain them with less bending and kneeling. Build your own raised bed this season, and enjoy the harvest for years to come.
Once you've built your bed, moving it won't be easy, so determine the best location first. Choose a spot that gets full sun for at least six hours a day —ideally more if you plan to grow vegetables such as tomatoes. Situate the bed least several yards away from any roads to avoid contaminants from traffic pollution. Raised bed flower gardens can add beauty to the front yard, while vegetable beds are generally better suited to the backyard. Many veggies can grow quite tall, put out long vines, or drop seeds everywhere, which some might consider a nuisance or eyesore.
Think about which plants you want to grow in your raised bed. Almost any kind of vegetable will thrive and produce in your bed as long as it's deep enough. Peppers, tomatoes, beets, and melons will do best in soil 12 to 24 inches deep. Plants with shallower root systems, including lettuce, spinach, radishes, and most culinary herbs, do fine in 6 to 12 inches of soil. Consider your cultivation goals when deciding how much material to purchase for the bed.
The cost of building a raised bed can vary greatly depending on material type and bed size. Many beds are made of lumber, but materials such as cinder blocks, logs, and old reclaimed wood work fine, too. If you choose to use lumber, pine boards are generally the cheapest option. One downside to pine is that it's not very rot-resistant, so boards could need replacing after a few seasons. Cedar boards are naturally rot-resistant and will last much longer, but they are more expensive. Board thickness also factors into the cost. You'll need boards at least one inch thick. Thinner boards might be cheaper but can't stand up to the weight of soil and plants.
For one bed that's 12 inches deep, you will need four 4-foot boards and four 8-foot boards that are each 6 inches tall. You'll also need four 12-inch balusters or wood posts at least 1 inch thick, to serve as corner supports. You can add more supports to the center of the bed, if desired, for increased stability. Additional supplies include galvanized screws or nails and a drill or hammer. Most home improvement and hardware stores will cut the boards for you, or you can use a handsaw to do the job yourself.
Before you begin to build, clear the garden site of any weeds and grass. Pull up weeds by hand or, if the area is overgrown, consider solarizing it. To solarize, mow the area as close to the ground as possible, then wet it thoroughly. Put a piece of clear plastic sheeting over the site, then weigh down the edges with a bit of soil, rocks, or other heavy objects. Over four to eight weeks, the sun's heat should kill nearly all of the growth. After weeds are removed, dig up a few inches of sod and loosen the soil below with a shovel or pitchfork.
Lay out the 4-foot and 8-foot boards in a rectangle shape. Using a drill and screws or a hammer and nails, secure one 12-inch post or baluster to the corners of two 8-foot boards. Next, drill or nail two 4-foot boards into each support. This completes the base of the bed. Repeat by attaching the remaining boards to the supports. If you'd like, you can attach more supports near the center of the 8-foot boards for more stability; two supports for each side should suffice.
You'll need 2.4 cubic yards, or 64 cubic feet, of soil to fill a bed this size, and there are several options. Bagged soils for raised beds are available at garden centers and home improvement stores, but this is typically the most expensive option and can get pricey if you want more than one bed. You can make your own soil mix to save money. One recipe combines 8 cubic feet of bagged topsoil, 6 cubic feet of composted cow manure, 6 cubic feet of coconut coir, and a 2-inch layer of grass clippings or shredded leaves. A third option is to buy soil in bulk and have it delivered; this is most cost-effective when ordering a large amount for several beds, since many companies charge a hefty delivery fee.
Plants in your raised bed will need to be watered more frequently than those in the ground, as the soil dries out quicker. Hand watering with a hose or pail is fine but can get tiring in dry areas where you need to water a few times a day. A sprinkler or irrigation system takes all the work out of watering, and can be connected to a timer to run at any time and frequency you want. These systems connect to your hose spigot. You might want to install a splitter on the spigot, which allows you to use the hose and the irrigation system at the same time.
Raised beds don't get attacked by as many pests, but that doesn't mean they're completely nuisance-free. Plants like broccoli and cauliflower are very attractive to moths and butterflies, whose larve will quickly destroy the leaves. Keep them off by draping a fine mesh net over the plants. This kind of net stops birds and other critters from eating your fruit, too. Beneficial insects — ladybugs, predatory mites, dragonflies, and praying mantises — keep bad bugs off your plants naturally.
Your raised bed won't need as much maintenance as an in-ground garden. Weeds are far less of a problem, but some may still appear, so be sure to pull them promptly before they can overtake the bed. You will need to add fertilizer throughout the growing season; which kind and the amount depends on the plants you grow. Mix in a bucket of compost every season to keep the soil healthy and replenish lost nutrients.