The bed’s 4 sides each need 3 courses of timbers to rise more than a foot above ground, for a total of 12 timbers. Because it’s best to have full pieces on each side, buy stock lengths at least as long as the dimensions of your bed. Make sure each timber is straight and clear of knots on at least one side.
to make a railing to cap the bed’s walls
to secure the first course of timbers to the ground. These are usually sold in 18- to 24-inch lengths. Both are long enough to secure 6x6 timbers at least a foot into the ground.
such as Timberlok and Timbrex brands, to fasten the sides together.
to fasten the railing to the timbers
for drainage under the walls and at the base of the bed. Most home centers carry either 1/2- or 1-cubic-foot bags. To determine the cubic footage you’ll need for 3 inches of fill at the base, divide the square footage of your bed by 4. To figure out how much you’ll need for 2 inches of fill under the timbers, add the length and width of the bed (in feet) and divide that number by 6.
Most home centers carry 2- or 3-cubic-foot bags of properly amended soil. Because the bed is just about 1 foot deep (with the gravel layer at the bottom), the square footage of the bed roughly equals the cubic footage of soil you’ll need to fill it. Throw in an extra bag to account for settling.
For fastening 2x8 cap rails.
So last summer’s homegrown tomato crop was more of a bummer than a bumper, and after a few exploratory backyard digs it seems less likely that you’re going to hit pay dirt. But that doesn’t mean going hungry. By building a raised planting bed, you can set up your seedlings with a loamy home as fecund as the Fertile Crescent.
Surrounded by timbers and filled with rich soil, the raised bed lets you customize your plants’ nutrients and moisture. It also brings the garden to the gardener, allowing you to easily maintain your plants without stooping.
And if you build it early you can get a head start on the planting season because the elevated soil heats up sooner than the ground. Then not only will the handsome structure help define your garden but never again will bad dirt stand between you and a good BLT.