The Keys to Stunning Window Boxes

A home accented with beautiful window boxes, perfectly appointed with seasonal flowers, exudes a charm that is unparalleled. However, there are many elements that come into play—from ease of watering to sun exposure and the right combination of plants—that can make this endeavour a bit daunting. That’s why we tapped Nancy Burton, co-owner of In the Garden in Highlands, NJ, whose passion is educating fellow gardeners of all levels, to share her expertise on how to create stunning arrangements that anyone can achieve.

Consider your water source. “When deciding on a location for your boxes, always take into consideration being near a water source,” Burton says. It’s so disappointing to have created a beautiful box only to realize the the task of watering it is next to impossible. Make sure you place your window boxes near a window that can be easily opened for effortless watering. You will have to do do this several times a week so make sure it’s not a difficult task.

Know your lighting exposure. Before heading to your garden center, Burton advises you familiarize yourself with the daily lighting exposure the container will receive. Use the information you gathered to determine if high light (5+ hours of bright sun), or low light (shade to part-sun 4 or less hours of bright sun) plants will be needed. Share your findings with your garden professionals so they can guide you to the perfect plants for your conditions.

Choosing your plants.  A good rule of thumb is to choose an accent trailing plant, one of two bloomers and a plant that can provide some height. “Most accent and foliage plants can handle part sun, such as asparagus, trailing vinca, ivy and dracaena spikes,” Burton shares. “So always start with a one to three of those varieties.” Then choose a bloomer or two that will work for your location (Lobelia and Bacopa are show above). There many colorful annuals available for all lighting conditions, Burton notes, so choose what represents your style and home. Achieve height by adding one or two taller plants, such as salvia, which is also shown above.

Good drainage is imperative.  “Check to make sure your planter has proper drainage holes—and drill them before planting if need be,” Burton says. “For a 28” box we recommend drilling three half-inch holes.” It’s also a good idea to place broken crock or medium size pebbles on and around the holes to improve drainage. Without proper drainage root rot will occur, which plants rarely bounce back from.

The basics of planting. It’s best to fill the window box two-thirds full with fresh potting soil every year. “Potting soil is lightweight and allows the roots to grow easily and quickly, keeping your plants healthy,” Burton instructs. When planting, work from the back to the front, making sure your tallest plants are centered and placed in the rear.  The accent and cascading blooming plants can then be placed in the front of the display, with any trailing material spilling over. To keep your box tidy, trim off any material that was damaged during planting.

Take good care. While this may seem complicated at first, caring for your window box will become second nature in no time. Shady locations will require less water, while sunny spots may need water every day to every other day. “Remember the soil area is very small so the planters will dry out more frequently,” Burton says. Fertilizing is also very important, as it promotes the plants to produce more blooms quickly. Burton likes using a time release fertilizer, as well as a water soluble type. During the spring and summer growing seasons, fertilize once a week.

Don’t forget to deadhead. The practice of deadheading removes past flowers after they have bloomed. “This process tricks the plant into reblooming,” Burton says. “Rather than finishing it’s life cycle and producing seeds, it will burst forth with fresh blooms.” At the base of the spent flower, simply pinch it off with your thumb and index finger. Keep up with this task and you will be rewarded with plentiful, showy flowers throughout the growing season. And undoubtedly, the envy of your neighbors.

TSG Tip 263  from Nancy Burton of In the Garden in Highlands, NJ. In the Garden is featured in the The Scout Guide Two Rivers and The Shore.