unique garden idea fence mounted flower box with window featured image

DIY Flower Box & Window for the Fence

Mounting a flower box and window to the fence is the perfect way to add some vertical interest to your garden.

fence mounted flower box & window unique garden design

I’ve been slowly working on creating a little garden oasis in a corner of my backyard. (It’s one of my 2019 Home Project Goals! ) It started last fall when we planted a crepe myrtle tree. Then I planted a few hostas that I found on the end of season clearance rack. (Because how can you pass up $.50 perennials?) Then some random bulbs. (Crocus?) And now, more hostas, day lilies, a sad little azaela bush, and a few others.

My flower bed filled up pretty quickly, but I wanted a way to add some height and more color. When I spotted this old window while cleaning out the garage I knew it would be a perfect fit! 

diy cedar picket flower box for fence

I mounted the window using a couple scrap 2×4 boards and then built a flower box using a few cedar fence pickets and some scrap pieces from my Big X Wood Quilt. I love how this idea came to life, and now I’m dreaming up ways to add more flowers to this pretty corner. 

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  • 3 cedar fence pickets
  • scrap pieces from Big X Wood Quilt OR an extra cedar fence picket ripped into 1-3″ strips
  • (1) 2×4 for mounting window & flower box to fence
  • (2) L-shaped brackets to mount flower box
  • old window
  • wood glue
  • nail gun with nails
  • wood clamps
  • table saw
  • miter saw
  • drill & outdoor screws
  • tape measure
  • level
fence mounted flower box unique garden design

Final Measurements of Flower Box

This completed flower box measures 36″ long, 7.5″ deep and 6″ tall. 

Build Your Flower Box

Cut List – cedar fence pickets

  • (3) @ 36″ (front, back & bottom pieces)
  • (2) @ 5.5″ (side pieces)
  • (1) 2″ wide x 36″ long (bottom piece – cut to fit)
  • Scrap pieces from Big X Wood Quilt or a cedar fence picket ripped into 1-3″ strips and cut at 45 degrees on one end

1. Cut your box pieces

I wanted to make my flower box the same width as my window which was 36″. If you are also using a window, measure your window before you start cutting pieces for your flower box. If your window is not 36″ wide you may want to adjust the flower box plans to match the actual width of your window.

I recommend waiting to cut the last bottom piece (2″ wide x 36″ long) until you are putting your box together. That way you can cut it to the exact width you need.

If you don’t have scrap pieces from making the Big X Wood Quilt, you’ll need to rip a fence board into 1-3″ wide pieces. Then cut these pieces down with a 45 degree angle on one end.

2. Add the decorative pieces

After you have cut your main box pieces you can start adding the 1-3″ wide strips of cedar on top. Line up the 45 degree end with the top edge of your front and sides pieces. I didn’t add any decorative pieces to the back board for the flower box since it won’t be seen.

diy cedar fence board flower box

Secure these pieces using wood glue and a nail gun. If you don’t have a nail gun, you can secure them by using wood glue and clamping them overnight.

backside of pieces for diy hanging flower box

3. Trim the overhang

Trim down the overhanging decorative pieces with a table saw. Set your guide to the width of your cedar board. Then run your front and side pieces through to trim off any excess. If you don’t have a table saw, this step can also be done with a jigsaw.

Trim down pieces on table saw
diy cedar fence picket flower box

4. Build your box

All that is left to do is build the box. Put your box together using wood glue and a nail gun. I recommend clamping the box and letting it sit overnight to make sure your glue dries securely.

Attach the front and back pieces to the ends of the side pieces. This is a little hard to explain, but look at the picture below and it should make more sense. The side pieces go inside the front and back pieces.

fence mounted flower box unique garden idea close up

Attach your last 36″ cedar board to the bottom of your flower box. There should be a gap of about 2″ left on the bottom of the flower box. Double check the measurement and then rip your last board to fit.

Before I added the bottom piece, I drilled a few holes through the board for drainage.

Mount the Window & Flower Box on the Fence

Cut List

  • (2) 2×4 @ 31″

Add 2×4 supports to fence

To mount the window & flower box onto the fence, I first attached (2) 2x4s to the fence. My fence measured 31″ between the horizontal supports, but you should measure your fence before cutting your boards. 

Attach your 2x4s so they are the same distance from each other as your window is wide. For me this was 36″. Screw them into the fence with a few exterior wood screws and you’re ready to mount the window.

fence mounted flower box and window

Attach Window & Flower Box

I drilled straight through the corners of my window to attach it to the 2x4s on my fence. 

mount brackets to fence for diy cedar fence picket flower box

I mounted my flower box using 2 L-shaped brackets. Screw the brackets into the 2x4s. Then, place your flower box on top. Use screws to attach the brackets to the bottom of the flower box and you’re done!

unique garden idea, fence mounted flower box & window

This cute little flower box adds so much color and character to my backyard! I love that it adds some height to my garden and gives me a spot to plant annuals. 

diy flower box for your fence woodworking tutorial pinterest

I want to hear from you!

If you use this tutorial, please let me know! Share a picture with me on Instagram or on the Mama Needs a Project Facebook page. Happy building!