Plotting a Garden Site for Your Raised Bed Garden

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Plotting a Garden Site for Your Raised Bed Garden
Before construction of a raised bed garden can begin, plotting the site is crucial, according to Steve Upson, horticulturist with The Samuel Roberts Noble Foundation headquartered in Ardmore, Okla.

Although level sites are sometimes in short supply, they are best for raised beds, Upson said. However, sites that are uniformly sloped, and not too much so, are quite usable for raised bed gardens. Below are steps on how to best utilize and plot your garden site.

The Procedure: Plotting the Site
Plot the adequately prepared site with grade already established (level or uniform slope). This will require, in addition to the materials listed earlier, a carpenter's square, several small and large nails, twine or heavy string, eight wood stakes, measuring rod, a permanent marker, and two measuring tapes long enough to reach across the plot.

Mark one side of the plot, preferably parallel or perpendicular to a nearby building, road, fence line, etc. running east-west or north-south. If such is not available, use a compass to establish the first side. Drive two stakes (points A and B) several feet farther apart than the actual planned plot length. String a line between the two points. Press a large nail into the ground directly under the string at the plot's corner point (point C). Place a second nail at an adjacent corner (point D). Line CD represents one side of the plot.

Measure the distance to both corners on the opposite side (points E and F) and mark with nails. Use a framing square to make points C and D a 90-degree angle, then make sure corner C (points F, C, and D) forms a 90-degree angle, using the 3-4-5 triangle ratio.

A 90-degree angle is established at corner C by measuring a point 24 feet from point C and marking with a nail under the string. Attach two measuring tapes to the nails at points C and G. Place a nail at the union (point H) where the 32-foot and 40-foot marks of the tapes meet. Remove the tapes and attach a string between points C and F. Make sure the string is taut, but not enough to move the nails. If the string is not directly over point H, adjust point F accordingly. Corner C should now be a 90-degree angle. If the distance between points F and E are not the same as between points C and D, adjust point E. This should now make corner D 90 degrees.

If the lengths are unequal, follow these steps: 1. Adjust the location of only points E and F. 2. Move the nails in one direction along line EF, never towards or away from points C or D. 3. To make an adjustment, move the nails in the same direction and at equal distances.

Prepare eight 2-inch-by-4-inch-by-24-inch wood stakes. Drive a small nail into the broad, 4-inch side of each stake, 4 inches from the top. Place the stakes 18 inches from each corner, centering them on each boundary line. Drive the stakes into the ground a few inches (temporarily) with nails facing away from the plot. Select one stake and drive it to a height above the soil equivalent to the bed height (height of rubber board). Use a leveling instrument and leveling rod to establish remaining stakes at the same elevation (unless slope makes this impossible).

Establish the position of each boundary. Attach strings to the nails on each stake, placing strings over the tops of the stakes. Be sure each string is taut and use a carpenter's level or plumb bob to position strings directly above nail points. Mark the position of each string along the tops of the stakes with permanent marker or pencil.