Turn a pallet into a wall-mounted garden!
Step 1: Prepare Pallet
Prime and paint the outside-facing surfaces of the pallet with an exterior-grade paint. Spray the inside surfaces of the pallet with 2 coats of Thomson's Water Seal or similar product to extend the life of the wood. If you don't want to paint your pallet, spray the outside of the pallet with sealant as well
Step 2: Attach Landscaping Cloth
The back of the pallet will need to have one piece of wood on the top and one piece on the bottom for support and to secure the pallet to the wall later on. The other pieces of wood should be removed. It will be easier to attach the landscaping cloth with fewer pieces of wood and the final product will be lighter on the wall.
Decide how many pockets you want to have. I went with 3 pockets. 1 small, shallow pocket at the top to plant trailing begonias and 2 deeper pockets (the depth of 3 deckboards on my pallets) for coleus.
Use a staple gun to attach landscaping cloth to the pallet. Cut a piece of cloth so it is the width of the front deckboard plus the width of the side and middle runner boards (I also left some extra to make room for error). Begin by stapling the top of the cloth to the front deckboard. Push the cloth into the corner and staple into the corner and then to the side runner boards. Continue to staple into the corners and into the side runner boards. Now fold the cloth where the bottom of the pocket is going to be and staple it to the deckboard. Fold the corners of the fabric so that they are inside the pocket and then staple the fabric in place. Now work your way back up to the top of the pocket, stapling the excess fabric to the runner boards and overlapping it with the fabric you attached when creating the front pocket.
Trim any excess fabric and then repeat the process for the remaining pockets.
Step 3: Mount Pallet
The pallet is mounted using 2 36-inch pieces of zinc-plated slotted angle. The 2 pieces will be used to create a mount that the the top rear deckboard will hang onto. Begin by determining how high your pallet will hang and mark this height on your wall. Measure the width of the top board on the pallet. Measure this distance down from top mark and then use a level to mark draw a horizontal line on your wall through this bottom mark. Line the bottom edge of one of the slotted angle backets up with this line. Mark to locations of 3 of the circular holes on the brackets and then drill holes in those spots. My pallet was hung to a wooden shed, so I drilled through the plywood and used carriage bolts, washers and bolts to secure the bracket to the wall. (If you attach to a different type of surface, the method of securing the bracket will be different. Keep in mind that the pallet will be quite heave once filled with wet soil).
After securing the bracket to the wall, measure the distance between the side and center runner boards. Use a hacksaw to cut the second piece of slotted angle so that it is an inch or two smaller than these openings. Attach one of the cut brackets to the one on the wall so it creates a U shape. Secure the 2 brackets together with 2 nuts, washers and bolts. Attach the second bracket the same way leaving enough space between the 2 brackets to allow the center runner board to fit in between.
When everything is attached, hang the pallet on the U bracket.
Step 4: Fill and Plant
Because of the weight of the dirt, we've waited to fill the planter until it's been hung. Use a lightweight potting soil mix to fill the pockets.
Choose plants that are suitable for the light conditions where your planter will be and begin with small plugs. Working from the bottom of the pocket, use a blade to cut 1 to 2 inch slits in the landscaping fabric. Open the slit and push some of the dirt aside to make room for the plug. After finishing a layer, press down on the top of the soil to secure the dirt around the roots. Continue planting and then water well.