How to Build a Wooden Window Planter Box


Wooden window boxes add charm to a home and increase the visual curb appeal. A simple wooden window box is low cost to assemble and painted in a color that coordinates with the home. You can alter the size of a standard window box to various sizes and shapes for use in the home or on a patio or porch. Purchase plastic liners from garden supply stores to prevent water damage to the box and increase the ease in planting.

Step 1

Measure the exterior window length and calculate the desired finished length of the window box. Common window box sizes are 30 or 36 inches long.

Step 2

Cut a front and back piece 36 by 6 inches. Cut the bottom pieces 36 by 8 inches and two side pieces 6 by 6 inches. Adjust the 36-inch length to the calculated length in Step 1 if needed.

Step 3

Add drainage holes to the bottom piece by drilling a 1-inch hole into the center or a 3/4-inch hole on each side two inches from the short edge. Sand the wood pieces with fine grit sandpaper to smooth rough areas and edges.

Step 4

Predrill 1/16-inch screw holes in each corner of the back, front and bottom pieces.

Step 5

Glue the back and front pieces to the side pieces with waterproof wood glue. Screw the pieces together with 1 1/3-inch screws using the predrilled holes.

Step 6

Glue the bottom piece to the top of the wooden window box with waterproof wood glue. Secure the bottom piece by screwing 1 1/3-inch screw through the predrilled holes.

Step 7

Drill a 1/2-inch hole into each top back corner 1 1/2 inches from the top of the wooden window box. Hold the window box to the desired mounting location and mark the hole location on the house.

Step 8

Install a hanger bolt at each marked location on the house by drilling a 1/2-inch hole and screwing the bolt in place so 2 inches stick out. Place the window box onto the protruding bolts through the holes on the backside. Secure the box with a washer and nut.

Things You'll Need

  • 2 wood boards, 1 inch by 8 inch
  • Saw
  • Sandpaper
  • Drill with bits
  • 12 screws, 1-1/3 inch
  • Wood glue
  • Hanger bolts
  • Washer and nut


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Keywords: wooden window box, make window box, build window box

About this Author

Jennifer Loucks has over 10 years of experience as a former technical writer for a software development company in Wisconsin. Her writing experience includes creating software documentation and help documents for clients and staff along with training curriculum. Loucks holds a Bachelor of Science major from the University of Wisconsin - River Falls specializing in animal science and business.