Window flower box planters add charm and character to your home. I have been dreaming about how to decorate my window planters for each holiday and season. However, before I get ahead of myself, I would like to share how to build window boxes quickly.
I knew I wanted to make my little studio so charming I would like to spend all my time out there. It had woodpiles, bags of Quickrete, empty flower pots, and tools on the porch and stacked up along the outside walls. It was an eyesore.

Window Flower Box
How to Build a Window Box
Mr. Kippi built me an Adirondak chair and an obelisk for my little secret garden next to my studio. I stood back and looked at the prototype obelisk and chair with the window and old rain gutters. At that moment, I knew the window needed some finishing touches to add beauty. I wanted everything to coordinate with other outdoor home improvement projects I have done, so the white window got natural wood shutters and a window box to add to the home’s curb appeal.

My inspiration for the window box was the chair and obelisk.
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I searched for inserts for the window boxes. Those inserts would determine the size of the window boxes could be. I choose this window box insert since they had a drip tray. I found this cute window box made by my friend, Rachel, that I adore, so I wanted one too.
Supplies and Tools
- 1 x 6 x 8 pressure-treated lumber
- 5/4 deck board pressure-treated
- Nails 1.5″ galvanized (box assembly)
- Nails 3/4″ galvanized (trim installation)
- Glue Titebond
- Window box insert with a water reservoir
- Wood sealer
- Paintbrush
- Sandpaper (100)
- Screws 2.5″ cabinet screws with washers
- Chop saw
- Table saw
- Drill (3/8″ bit for drain holes and 1/8″ bit for pilot holes)
- Clamps
- Nail gun
- Watering can
- Solar light
Planning
The first thing you will need to do is measure your insert and write down the height, width, and length. Note: take the measurements just under the upper lip of the insert if yours has one. Cut your (1 x 6 x8) lumber to accommodate those measurements.

Cut lumbar, and the flower box insert.

Box lumber cuts

Glue the end pieces

Glue on ends

Nail ends in place

Glue the front panel

Nail front panel

Measuring to be sure the box is square

Adding the first piece to the bottom

Adding the second piece to form the bottom
Installing Trim

Taking measurements for trim

Use a chop saw to cut trim pieces

Glue on trim

Nail trim pieces in place

Finished DIY flower box with insert

Checking the insert before water sealing and filling
- Water Seal, paintbrush and Handy Cup
- Apply Water Seal

Drill drain holes in the bottom of the box

Three drain holes
Installing Window Flower Boxes

Pre Drill 3/4 by 1-inch spacer board for hanging

Install spacer

Holding the flower planter box to be sure of the placement

Marked and pre-drilled holes for mounting screws
- Install hanging window planter with screws
Inserting the Flower Box Liner
The window flower boxes are on opposite sides of the studio, so they needed different plants since one was in the shade and the other one got a ton of sun (Florida sun). You can see how I choose the flower plantings HERE.

Adding the insert with flowers

Watering the planter after I filled it with flowers and plants
You can see the area behind the obelisk; it needs a trellis with a garden planter and lanterns. You can see how we built those gorgeous trellises HERE. Please join our newsletter, so you don’t miss a thing. I will be sharing how to make shutters, Adoranik chairs, and the obelisk with solar lights.
The new custom rain gutter looks so much better. I did not notice how awful the rain gutters looked until I installed the window box and shutters. I called and ordered the rain gutter and downspout over the phone and had them delivered. It was the right decision to replace them.

Studio garden area
This window box adds beauty both indoor and outdoor since I can see the flowers from inside too.

My custom made chair with a fresh mojito
I created a DIY side table from a fallen tree. We also made some super groovy live edge hairpin leg tables you are going to love. You can see them in this post. The vintage style pot with the transfers can make one, too, in this earlier post.

Side table made from a fallen tree

DIY Adirondack chair

DIY Chair, table, window box, and obelisk
If you love flower boxes and window box planters, you will enjoy building some and installing them on your home too.
You might also enjoy these other outdoor projects:
DIY Garden Trellis for your garden.

Lantern and Garden Screen Trellis
Learn how to Build DIY Lanterns with Solar Lights.

Handmade solar lanterns at night
DIY Floating Deck and watering station.

Wood garden floating deck

Finished deck and garden hose hook post
Learn to craft concrete outdoor projects with Quickrete.

Boho chic hanging planter
Step by Step, hanging planters.

Hanging Basket Step by Step Guide
Thank you so much for our visit today.
See you soon,
Kippi
Rebecca Celhar says
What an upgrade! It’s such a clever way to hide a plastic window box.
Kippi says
Thank you so much for stopping by. I am so happy with how it turned out.
Hugs,
Kippi
Jessica says
Wow that made a huge difference! And I love the draping plants!
Christine says
I’m really loving the window box!!! It really compliments the window shutters! Thanks for sharing!! I want to make some now!!
Amy @ Heritage Home Ec says
These are simply gorgeous! I need to do something similar for my windows also. I have the shutters already in place. Just need window boxes full of gorgeous flowers. Thank you so much for the inspiration.
Anita Holland says
So many gorgeous projects and simple to follow instructions. Pinned
Kim says
I’m loving this Kippi! I actually have a couple of window boxes on back order and am becoming impatient. I might have to try this instead! Love all the other projects too!
Kippi says
Thank you so much for stopping by today. You are so talented I know yours will be lovely.
Happy decorating,
Kippi
Allyson says
You said ‘workshop’ and bingo you gave me the idea that I can do this to the windows outside my husband’s workshop. Pinned. Thanks for the inspiration!
Jayne says
These are just gorgeous and much easier on the eye than plastic containers! I think this project looks easy enough for me to try too!
Kippi says
Thank you so much for your visit and kind comments. I hope you enjoy making some flower planter boxes too.
Have a beautiful day,
Kippi
Marie says
First, I’m so jealous of your sweet studio space, Kippi. The wooden shutters and planter box is awesome and really dresses up the window. Love the seating area you created below it too. What a wonderful spot to work and create in.
Kippi says
Thank you so much for your kind comments. Have a beautiful day,
Kippi
Linda says
I’m so excited you’ve been PINKED! Thank you for sharing on the Classy Flamingos. http://blog.poinsettiadr.com/2020/05/classy-flamingos-blog-party-104.html
CoCo says
These flower boxes are totally fabulous, Kippi! I love how you can take the flower tray in and out. That is genius and so convenient too! Everything about your studio space is so inviting. I just love it! Hope you’re having a great week, hugs, CoCo