How-To Ideas

Planting Window Boxes – Ready for a Challenge?

Window box in garden room

Thriller, filler and spiller the saying goes, this is my mantra as I stalk the garden centers looking for inspiration for my window box. My mind goes blank and my containers end up looking pretty much the same as last season. I’ve met my horticultural Waterloo.

Exploring a nearby neighborhood I found the inspiration I need and have begun to hatch my plans. Every garden starts with an idea and the seed has been planted in my mind to create the perfect window box.

Readers, I confess. Years ago I tried and failed. It’s hard to keep window boxes looking good. It’s all about location, location, location, so I’m sharing some things to consider in creating a beautiful window box.

Window Box Location

Take a long look at your window box location. Consider how much sun it receives throughout the year recognizing that conditions right next to a window are more intense. Glass can reflect the sun and burn tender plants while hard surfaces, such as brick and stone, absorb heat and release it throughout the night keeping the box much warmer, and drier than you might imagine. Keep in mind that nothing lasts forever—a chilly northern exposure might be the perfect place for a window box come spring while a south-facing spot may be the ideal spot in the fall. Decorative shelves or mini balconies can be attractive additions to your windows in their own right by adding interest to your home’s appearance with or without plants.

Materials Needed to Plant a Window Box

The construction of your window box will dictate the plants you select and their planting medium. The design possibilities for your window box are too many to list here: the Internet brims with ideas and a quick search on Google, Pinterest or Instagram can entertain for hours. Don’t let creativity get in the way of practical issues though. Be mindful of the weight of the container, plants, planting medium and water. A 36-inch long box can be surprisingly heavy so ensure you can anchor the box securely. Select materials that complement your architectural style but are hardy enough to endure harsh conditions and provide maintenance-free service for several seasons.

Watering a Window Box

Window boxes tend to be smaller and subjected to more heat than most container plantings so be prepared to water more frequently, sometimes multiple times a day during hot weather. My downfall was imagining I could fill containers and lug them to water my creations—it was a recipe for disaster. So select locations that have a tap nearby or install a drip system that can be operated by a timer.

Plant Selection for a Window Box

Window boxes are seasonal creations so plant for immediate impact. Better to trim and even remove plants when they exceed the space than to wait weeks for small plants to fill in.

As for which plants to select? This is the fun part and where I’ll sign off; your local garden center can help guide your choices. Start dreaming and make your plans for this season. I can’t wait to walk by and see what you create.

Lise Jenkins is a newspaper columnist and volunteers her time as a Durham County Extension Master Gardener. You can find her on Instagram @AbsenteeGardener.