My grandmother, an avid gardener, had plant beds all around her home, but some of my fondest memories are of the window boxes that hung beneath her front windows, overflowing with vibrant flowers—often geraniums.
Window boxes are perfect for flowers, herbs and other small plants, and they can instantly brighten the exterior of your home. They’re also an excellent solution if you have limited yard space but still want to enjoy gardening close to home.
While you can buy ready-made window boxes from many retailers, building one yourself is both satisfying and customizable. Below is a straightforward window box project you can tackle at home, then fill with your favorite plants. This guide keeps things simple and practical so you can create a durable, attractive box that fits your window perfectly.
Supplies
Pencil
Measuring tape
Electric drill
Screwdriver
Electric or manual saw
1-inch thick boards for the sides, front/back and bottom of your box (dimensions depend on your window size)
Medium-grit sandpaper
1.5-inch wood screws
Potting soil
Plants
Optional: exterior paint or stain and a box liner such as burlap for added protection
Instructions
1) Measure the window frame and trim to determine the appropriate size for your window box. If the box will sit on a window ledge, measure the ledge depth so the box fits securely.
2) Transfer your measured lengths onto the boards with a pencil and cut them to size. Lightly sand the cut edges to remove splinters and create a smooth finish.
3) Drill pilot holes at the joints to prevent splitting, then assemble the sides and ends first using 1.5-inch wood screws. Attach the bottom panel last. Drill several small drainage holes through the bottom to allow excess water to escape and protect plant roots from waterlogging.
4) Once assembled, sand any rough spots. If desired, apply exterior paint or stain to protect the wood from weathering. For additional moisture protection and to help contain soil, line the inside with burlap or another breathable liner before adding soil.
5) Mount the window box using appropriate brackets or hardware. For wood or siding exteriors, standard mounting brackets will work; for brick, stone or stucco, use a masonry bit and masonry anchors to securely fasten the brackets to the wall.
After mounting, fill the box with quality potting soil and arrange your plants with attention to sunlight needs and spacing. Consider mixing trailing plants with upright varieties for a fuller, more attractive display. Keep the soil moist but not waterlogged, and deadhead spent blooms to encourage continued flowering.
If you try this project, consider taking a photo of your finished window box to track your progress and inspire others. Happy building and gardening!