How to Build a Window Box

A simple Saturday afternoon project of a DIY window box and our home has added character, charm, and a bit of practicality.

After creating a space behind our home for a vegetable garden, we wanted to optimize the area and decided to add window boxes.  It only took one quick trip to the hardware store and a few hours one Saturday afternoon.

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WINDOW BOX SUPPLIES

• Brackets and screws
• Measuring tape
• Level
• Rectangular planters (grab these first as your board widths will depend upon the size of the planter)
• 4 Wood boards: base and front along with 2 sides (measure first and ask your hardware store to cut them to size)
• Drill
• Wood glue
• Nail gun
• Wood stain (optional)
• Weatherproof poly/stain/paint
• Potting soil
• Flowers or herbs

HOW TO BUILD A WINDOW BOX

1. Mount the brackets onto the exterior of your home.  We chose a simple L-bracket because it will not be seen and we wanted a sturdy bracket since a lot of weight will be placed on it.  Remember that the soil will add more weight than you would except, especially when it is wet.

To determine where to place the brackets, first, measure the length of your window and evenly space them 6-9 inches from either end of the window frame.  Second, measure the width of the board that will be the front of your window box.  The bottom of the L-bracket will need to be approximately that length down from your window frame.  {It really all depends upon the look you are going for.}

Be sure to use a level so that the window box is even.  {Side note: our house is old, so levels are used slightly and then we have to eye it the rest of the way.}

Using a drill, attach the L-bracket to the exterior of your house with screws.  To accomplish this, James used 2-inch screws that he already had.  (He needed a total of 20 screws that were 2 inches in length.}

The amount of brackets per window depends upon the length.  Typically, for a single window, 2 brackets are used and similarly, for two windows side by side, 3-4 brackets are necessary.

2. Secure the bottom board to the base of your L-bracket.  Be sure to measure and use shorter screws that will not go through the bottom of the board.

3. Apply a line of wood glue to the bottom 1/4″ of the front board.

4. James attached this board to the front of the bottom board in order to allow room for the planter to rest under the window frame.  Hold this front board in place for a little bit in order for the glue to set.

5. Using a nail gun, secure the front board to the bottom board.

6. Using the same technique of wood glue and nail gun, attach both ends to the planter.

Now, this is when I jump in and give a few caveats:

*We opted not to place a board in the back and to only have a base, front, and 2 sides simply to save a little money.

*Also in the interest of the budget, we purchased the cheapest wood: common board.  We did so with the understanding that I would waterproof it…plus, we will be painting our home within the next few years and these will be taken down.  If you have the budget for it: by all means, purchase pressure-treated boards.

*Due to the curve of our window trim, we did something a little different with one side of each window box, which you will see soon.

7. Add a stain to your boards (optional).  Afterwards, be sure to waterproof the boards thoroughly.  {I used the same product on these as I did on a porch flooring.  Click HERE to see!}

As I mentioned earlier, we did a little something different on one end of each window box.  James pre-drilled 3 holes to the side of the front and base board.

Using a drill and screws, I can remove and re-hang this side in order to slide the planter in and out.

HOW TO ADD HERBS TO A WINDOW BOX

1. As I mentioned earlier, measure your window and then find the appropriate sized window box before cutting your boards.  This is mostly to ensure that the depth of your bottom board is wide enough to fit the planter.  Our window lengths are slighlty longer than the planter, but that doesn’t cause an issue at all.

Since we have one single window and two side by side windows, we needed 3 planters.  Unfortunately, I could only find 2 black.  I improvised and picked up a green one and spray painted the top of it to match the others.

2. Using small stones, I spread out a thin layer on the bottom to help with drainage.

3. After checking out the heights of the various herbs, my daughter and I played around with different layouts prior to planting.

4. Fill the planter with soil and plant your herbs.

HERB GARDEN WINDOW BOXES

We planted basil and flat leaf parsley…

along with sage…

and some lavender and curley parsley.

{I am still absolutely smitten with the back porch makeover we did last fall.  The window boxes pulls all of these projects together now.  Click HERE for that porch makeover…it went from gross to our favorite “room.”} Our succulents are thoroughly enjoying this location as well.  {Click HERE for that update.}

This planter sits right outside our homeschool nook off our kitchen.  I am thoroughly enjoying looking out and watching it grow and am anxiously awaiting lavender blooms.

{HOMESCHOOL ROOM MAKEOVER}   {KITCHEN OPEN SHELVES}   {PAINTED KITCHEN CABINETS}

I am so excited to watch these herbs grow and to use them in my cooking.  Fingers crossed that I can add a dehydrator to our home so that I can preserve these fresh herbs and use them all year round.  {I have THIS ONE currently in my shopping cart.}

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