How to Build a Window Flower Box

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Trying to find flower box ideas? Look no further!

Window flower boxes usually have a width of 1 foot or less than 2 feet. The length of a flower box usually ranges between 1 to 2 meters, but the size typically depends on the location of the window where they need to be installed.

In some cases, flower boxes are installed outside of windows, or used for lining patios, steps, decks, porches, and sidewalks. Flower boxes are installed outside the windows with the help of flower box holders or wall brackets and are usually made from metal materials like iron, while traditional flower boxes are made of wooden planks. Softwoods like Scots Pine are used for making such traditional flower boxes.

Nowadays, flower boxes are made from many different materials, including plastics and specialized polymers, however, wood and metal boxes are still prominently sold.

Flower boxes installed outside the windows are also known as window boxes and are mainly used to plant flowering plants. However, they are also used for planting herbs or fruit-bearing plants as well as many other plants that are used for culinary activities.

Flower boxes can be installed outside your bedroom, hall, or kitchen windows quite easily.

Get started building a traditional flower box

There are so many different ways to build a flower box, some complicated and some quite simple. Many people opt to buy pre-made flower boxes from a nearby store; however, others prefer building their own boxes with materials that are readily available.

Building a traditional flower box will require some wooden planks and a few brackets. You will also need some basic tools that are used for attaching the brackets and the wooden planks.

Here are the steps required to build a traditional flower box:

Step 1: First, begin by measuring the length of your window. In this example, we’ll assume a measurement of 3 feet in width.

Step 2: Next cut out your wooden planks to match your window measurement. You will need 3 boards measuring (1” x 6” x 3′). These will serve as the bottom and length-wise sides.

Step 3: Then cut out 2 end caps which measure at (1” x 6” x 5”).

Step 4: Now drill in 3 water drain holes, evenly distributed across one of the (1” x 6” x 3′) boards that will serve as the bottom piece. Alternatively, if you do not have a drill, you can repeatedly use a screw, but I’d recommend creating twice the number of holes.

Step 5: With all of the wood pieces cut out, it’s time to assemble the flower box. Take the bottom board with drain holes and apply your wood glue all along the 1” left side. Then line up the ends of one of the (1” x 6” x 3′) boards to this glued side. Once it’s perfectly flush, you will put in 4 nails, equally distributed along the edge, so they connect both boards together.

Step 6: Flip the box over so that the newly attached side is face down, and apply wood glue to the 1” right side of the bottom board. Repeat the process again, attaching the 3rd (1” x 6” x 3′) board, and hammering in 4 equally distributed nails.

Step 7: Once both sides are attached to the bottom board, flip the flower box over so that the bottom board is on your work table.

Step 8: Take your wood glue and apply a line on the edge of both sideboards, and the bottom board. Then insert your first wood end cap into the box. Be sure to put this INSIDE of the box, and not on the outside. This end cap is intentionally cut 1” short as to fit into the box snuggly.

Step 9: Once the end cap is fitted flush inside, use two nails to carefully nail in each side of the end cap to the sides in order to secure them.

Step 10: Now repeat the end cap installation process for the other side.

Step 11: Next you will need to nail the flower box holder’s brackets carefully under your window. Make sure to equally distribute the brackets to evenly distrubute the weight it will be holding up. Some flower box holder’s come with their own directions, be sure to read any requirements.

Step 12: Finally, you can add the flower box liner into your flower box. It’s now ready to be mounted and filled with dirt, or pots, and your favorite choice of flower box flowers!

And with that, you’ve built a traditional window flower box!

What to do next?

If you wish to skip building your own window flower box and jump to planting your plants directly into a pre-made window flower box, you can buy them online or at your local retail hardware stores at a reasonable rate.

Additionally, you may also want to perform additional decorative steps, such as staining or painting the wood to your preferred color, or cutting out additional pieces of wood to provide an outer trim to your box, giving it more detail.