DIY Raised Gardens

Raised gardens improve soil drainage, prevent soil compaction and extend the growing season. Such gardens are composed of piled dirt in framed or frameless structures that are higher than the surrounding ground. While temporary, frameless raised gardens are the most inexpensive and simplest to construct, they only last one growing season. Depending on personal preference, you can use railroad ties, landscape timbers, concrete blocks, bricks, rocks, stones, heavyweight plastic or metal strips to create frames for a raised garden and fill it with quality soil.

Things You'll Need

• Landscape timbers
• Saw
• Powdered chalk
• Shovel
• Wheelbarrow
• Gravel
• Marker
• Hand drill
• 12-inch metal rebars
• Sledgehammer
• 10-inch timber screws
• Quality topsoil
• Peat moss, compost or manure

Instructions

1. Lay landscape timbers over the selected spot in your yard to form a square or rectangular outline. Ideally, a rectangular raised bed with a width up to 4 feet is suitable for growing plants and vegetables. Fit the lengths of timbers so the edges lie flush against each other to form the outline in your desired dimensions. Cut additional wood length if necessary.

2. Spread powdered chalk along the inner and outer lines of the timbers or cut through the soil along both sides of each timber with a shovel. Remove the timbers, and strip the sod or grass growing within the outlines. Remove 4 inches of soil within the outlines and pack in a wheelbarrow. Level the base of the trench.

3. Spread 2 inches of gravel over the trench and level with the back of the shovel. Lay the four landscape timbers over the gravel with the ends flush against one another. Place a level diagonally across the tops of the timbers to check that the forming bed is even, and add or remove gravel to align, if necessary.

4. Mark a spot every 3 feet apart along the four timbers. Drill a 1/2-inch pilot hole through each mark. Insert a rebar into each hole and drive it all the way through, using a sledgehammer. The lengths of rebar penetrate the gravel and soil under the timbers, and hold them firmly in place.

5. Lay another row of identical landscape timbers over the previous row. To join this row to the one below it, drill a 10-inch timber screw through the corner of each length. Also drill one screw through the middle of each timber for added security. For a higher garden, lay another row of timbers over the second row and join with timber screws.

6. Add 3 inches of gravel into the base of the raised garden and level. Fill it with quality topsoil along with organic soil amendments such as peat moss, manure or compost until 3 inches from the top.

References

• University of Missouri Extension; Raised-Bed Gardening; Christopher J. Starbuck; Match 2003
• This Old House; How to Build a Raised Planting Bed; Harry Sawyers
• AgriLife Extension Texas A&M System; Building a Raised Bed Garden; Priscilla Files et al