Window Box Gardening


by Karen Weiland, Advanced Master Gardener



Window boxes can add cheer to the exterior of your home no matter what season of the year it is.  They can be amazingly versatile, cuttings of evergreens with some berries and pine cones during the winter, daffodils for the spring, chrysanthemums and pumpkins in the fall and a mixture of annuals in the summer.  Not only can they look good viewing them from the outside, they can also add beauty viewing through the window from the inside of your home.

Check out your homes exterior to see which windows need sprucing up.  I choose my kitchen windows.     Some of my other windows have little welcome lights in them and I thought bringing some light along with flowers would be just the touch I was looking for.  Select a design that works well with the architecture and color of your house, shutters and trim and choose a box that is the same width as your window.  Take into consideration that the plants in a window box can act as a screen if you have close neighbors or an unsightly view from a particular window.

You can fill the box itself with soil or do as I did and purchase some rigid plastic planters that fit into the box.  Actually, I bought the plastic planters and built the window box to fit them.   Make sure the window box has drain holes so water does not fill it during a rain.   If you opt to fill the box itself with soil, place coffee filters over the drain holes and place about a one and one half inch layer of pea gravel in the bottom for better drainage, then top that with some landscape fabric and soil.  You are ready to choose plants.

A couple of important things to consider when choosing annual plants is the amount of sunshine or shade the plants in the box will get and how big the plants will be once they are fully grown.  I placed some coleus in mine and have to keep it trimmed so if you do the same, make sure you can easily reach the plants for trimming.  Once you have chosen your plants, arrange them in the window box until you are happy with the design you have, both from inside the house and from the outside.  A little crowding is ok but make sure you can get to the box for trimming the over-achievers.  You can also just drop the plants, pot and all, into the box for swapping out if it doesn’t perform like you had hoped it would or for popping in something seasonal.

When choosing plants keep the trio of thriller, spiller and filler in mind.  Choose a thriller to catch the eye, a spiller that will cascade over the side and a filler to pull it all together.

Regularly check the soil, daily during hot weather, and water well when the top inch feels dry.  Nutrients wash out quickly in containers, so using a fertilizer is recommended.  Don’t skimp on the soil, use a high quality potting mix.

Oh, and one last note. I laid out a string of clear lights through the flowers in my boxes and put them on a timer.  My flower boxes have a glow starting about nine o’clock every night!  It’s so pretty!


As always, Happy Gardening!



More information about gardening and related subjects is available online at    The Purdue University Cooperative Extension Service can be reached at 499-6334 in LaGrange Co., 636-2111 in Noble Co., 925-2562 in DeKalb Co. and 668-1000 in Steuben Co.