How to Build Tiered Garden Boxes

Choose a Site

• 1

  Choose a site that will get at least 6 hours of sun a day. Make sure the tiered boxes will be sited away from overhanging trees and structure walls that will shade them.

• 2

  Check your micro-climates and avoid low spots where frost and cold air will collect. Planting can be done earlier in the year and plants held in the garden later if the site is in a warm spot on the property.

• 3

  Note the way the winds blow across the property. Do not site the tiered boxes in the face of prevailing winds. Plants will dry out in summer and windburn in winter.

Make the Boxes

• 4

  Choose common dimensional lumber for this project. It could also be made from cedar, recycled lumber, or any dimensional lumber of the same size.

• 5

  Make sure the boards are straight and without large cracks. Check for cupping or arching by laying each board flat on a level surface. Check for bowing by holding the narrow side of one end of the board up just under eye level. Close the other eye and sight along the narrow edge of the board. If the board is curved discard it.

• 6

  Paint the lumber with non-toxic wood preservative, including the ends. Let the lumber dry for the time recommended by the preservative manufacturer. Lumber need not be treated if you intend to let it weather and chip it up for mulch or compost later.

• 7

  Cut two 8-foot boards into 4-foot pieces.
  Cut the remaining 8-foot board into four 2-foot pieces.
  Cut the 6-foot board into two 3-foot pieces.
  Cut the 12-foot board into two 6-foot pieces.

• 8

  Make boxes using simple butt joints nailed together. Use two 6-foot and two 4-foot pieces for the biggest box. Put together the middle tier box using two 4-foot pieces and two 3-foot pieces. Join the upper tier box using the four 2-foot pieces.

Assemble the Tiers

• 9

  Level the site you have chosen for the boxes. Put the lower tier box directly on the ground at the site. Put a 6x4 foot piece of weed-inhibiting cloth like Reemay inside it directly on the ground.

• 10

  Fill the box with a mix of garden soil and compost or purchased top soil and compost. Use 2 parts compost to 1 part soil. Level the soil and firm up. If the soil is dry water it. Watch for settling and level up as needed.

• 11

  Put the second tier box on the soil just inside the edges of the first box. You will have a 2x1 foot "L" of soil showing in the lower tier. Fill the box with soil, water and level up as needed.

• 12

  Put the third tier box on the soil just inside the edges of the second tier box. You will have a 2x1 foot "L" of soil showing in the second tier. Fill the upper tier box with soil, water and level up the soil as needed.

• 13

  Avoid using high pressure, heavy streams of water from the hose. The soil will splatter out of the boxes or wash out.