Planting Beds: Checklist

• Building the planting beds We had lots of ideas for inexpensive walls for the planting beds, ranging from scavenged lumber to old garage door panels. But we finally bit the bullet and built our own of 1/4" plywood. The problem is that anything wooden which is in contact with soil is going to eventually rot - the question is - how long before it does so and how much will it matter when it does. Perhaps it doesn't really matter. Here's what we did.
  • We cut widths of 1/4 exterior grade plywood into sections 20" wide. We made panels by sandwiching 2x2 between the 1/4" sections, with 2x2 running all along the perimeter, and vertically every 2 feet.
  • We combined several pieces of 8' plywood so that each finished panel was the exact length of the side or end of the planting bed that it would be used for, taking into account the thickness of the panels
  • We painted each panel with several coats of primer, and then several coats of exterior paint.
  • We then painted each panel with carpet adhesive for 'glue' and then applied 6mil plastic - wrapped around the panel to waterproof it.
  • We waited hopefully for this to dry - took forever, since the plastic kept the carpet glue from evaporating, but eventually it sort of did
  • We carried each panel out to the greenhouse and put them in place.
  • We caulked the edges where they'd join with silicone caulk, screwed them together with 4" screws, which went into the 2x2s at the ends of the panels, and caulked the screw holes.
  
  
• Filling in soil/rock Next we alternately filled in the planting beds and walking areas with dirt and rock. We quickly discovered that if we filled all the rock or all the dirt first, that the panels would bow inward or outward, depending where the fill was.
  • For the planting beds, we really wanted to use the best material we could. We are fortunate to live in the country and we knew our own soil was uncontaminated by pesticides. So we had a friend scrape 6 inches of topsoil from one corner of the property and bring it up to the greenhouse site. Plus we had the stockpiled topsoil
  • We had been making compost for a year, a lot of it.
  • My husband had happily found a source for leaf mould, and obtained about 12 big trash cans full
  • So the mixture that went into the planting beds was probably 1/2 to 5/8 soil and the rest 1/2 leaf mold and 1/2 compost. It was so fluffy that if you accidentally stepped into a bed it went down about 8". Of course, a year later it has settled about 2-3".
  • We ran everything through 4' x 4' screen that we made of 2x2s and 1/2" hardware cloth
  • We just laid a couple of 2x4s across a planting bed, plopped the screen on top, shoveled stuff in and worked it through with our hands and sometimes a shovel or hoe. Hands was fastest.
  • We added other amendments that seemed appropriate knowing our soil - llama doo, greensand, rock phosphate, alfalfa meal, kelp meal, etc
  • We also added more gravel between the beds until it was about 4" below the top of the concrete beam and perhaps 8-10" below the top of the planting beds
  • We added a tapered top of cedar - 1/2" x 4" to the top of the planting beds to sit on and to protect the plastic
  • We planted the beds (this was about late october), and added temporary netting to discourage rabbits
  
  

Overview | Sitework | Drainage, Insulation, Flashing | Stone & Gravel | Foundation | Planting Beds
2 x 4 Walls