Window boxes are coming back in style! They dress up a window and offer a gardener yet another place to grow flowers. They also brighten up a streetscape or a home’s façade with happy flowers and greenery. Having a window box is one of the most neighborly things you can do in the warmer months of the year.
In the early 20th century in the United States, window boxes were at their peak of popularity. Houses were being built on smaller lots, with many close to the street, and historical styles such as cozy English cottages and inviting Dutch colonials were in vogue. Window boxes were a perfect match. They also fit the 1920s Spanish and Mediterranean–style houses. The popularity of window boxes faded as suburban homes and large lawns became the norm.
I recommend using large window boxes if you want a flowerful display such as this one. Big window boxes can hold more soil and won’t dry out as quickly as smaller ones, allowing you to plant fewer drought-tolerant plants. Here, flowers and foliage were planted together, including the versatile lime-green sweet potato vine (Ipomoea batatas).
This deep window box drops into a black metal holder, which is visible beneath the flowers. Metal supports are a decorative and sturdy solution to supporting the weight of long window boxes. The trailing flower is ‘New Gold’ lantana, a heat-loving perennial (annual in northern regions) that blooms from spring to fall—excellent for tumbling from planters and hanging baskets.
Today, we are embracing apartment and townhome living. The smaller lots and patios have us looking again to window boxes (and modern deck-railing planters) to satisfy our thirst for gardening. For example, why not grow a small kitchen garden in a planter box hung outside a window? Imagine opening the window and harvesting some lettuce or nasturtiums to dress up a salad?
The considerations of proportion and scale are important when it comes to window boxes. A well-proportioned window box has an appealing look, but one that is too small looks silly. As for length, the box should extend several inches beyond the windowsill or shutters, if you have them. As far as width, I suggest extra-large window boxes that are wider and deeper than usual. How wide and deep is a matter of proportions, which is all in the eye of the beholder. A good rule of thumb is that the height of the window box should be 20 to 25 percent of the height of your window. If you use large brackets to support your flower boxes, add their dimensions to your calculations.