6 Cascading Flowers for Window Boxes That Will Add Beauty and Drama to Your Home's Façade

Cascading flowers, also known as spillers or trailing plants are truly a charm if you're seeking to add a bit of personality and color to your window. These blooms not only look good as a decorative extension of your home, but they also lend a subtle scent of freshness.

If you want to please your neighbors or simply wrap your window box with a touch of elegance, then cascading flowers might just be your saving grace. But what are the best flowers for window boxes to add drama and volume, that also don't mind being grown in these small containers?

Ready to spruce up your window box and explore this container gardening practice? Here are some precious blooms chosen by an expert.

An expert's pick of cascading flowers perfect for window boxes

Gardening expert and owner of Breemar Flower Farm, Nicole Dillion tells us: 'Cascading flowers and foliage take an ordinary window box and elevate it. You can apply the same principles for designing a container garden for your window boxes. You want to have a filler, spiller, and thriller. These three elements make for an interesting window box that captures the eye and makes them appear larger and more dynamic. A cascading element brings cohesion between your foundation plantings and your window box'.

Nicole Dillon

Nicole Dillon is a micro-flower farmer and owner of Breemar Flower Farm based in Ashland, VA. With a profound love for gardening, Nicole has transformed a passion for nurturing plants into a thriving business. Specializing in growing peonies and cut flowers, Nicole shares her expertise through a weekly blog aimed at home gardeners. Her mission is to inspire and educate gardeners of all levels, helping them create beautiful, sustainable spaces. Nicole also volunteers as a master gardener in her hometown. 

1. Creeping Jenny

Creeping Jenny, known as Lysimachia nummularia in the plant world, is a super hardy, bright and dainty perennial. It's green and gold foliage and trailing habits makes it an ideal window box idea.

Gardening expert Nicole Dillion from Breemar Flower Farm in Ashland, VA says: 'Creeping Jenny's chartreuse like leaves combined with hot pink or orange blooms really shine. I particularly like using these color combinations if your home sits off the road. The bright colors give massive curb appeal'.

Nicole says this fun loving plant tens to do well in 'full sun to part shade locations and holds up well for the entire season. It can tolerate occasional dry soil conditions'.

Plant Hardiness Zone: 4-9 ( United States Department of Agriculture -USDA)
Sun exposure: Full sun to part shade

2. Sweet Alyssum

Sweet Alyssum are lively blooms with a fragrance that is absolutely irrespirable. If you're looking for low maintenance garden ideas, then you should consider adding these into your window boxes. They're easy to grow and are delicately grown into a variety of shades and colors.

'If your window boxes are close to an entryway, consider planting Sweet Alyssum because of its honey-like fragrance. What a lovely way to welcome guests! These tiny delicate flowers fill a window box with vigor and cascade over their planter quickly,' Nicole says. 'The most common color is white, but pink and purple varietals are also available, especially if you're willing to grow it from seed. Sweet alyssum is best grown in full sun but can also take partial shade. Allow the top two inches of soil to dry out before watering'.

Plant Hardiness Zone: 5-9
Sun exposure: At least 6 hours of full sun. It can tolerate partial shade.

3. 'Silver Falls' Dichondra argentea

Dichondra argentea, or the 'Silver Falls' is known for its vigor and evergreen characteristics. This silvery leaf plant for the garden is a tender perennial, but it is usually grown as an annual. It's small green and fan-shapes appearance, with hints of white add a unique touch in any space its grown.

Nicole says, 'If you're drawn to silver elements in a garden, look no further than Dichondra 'Silver Falls'. It pairs beautifully with pastel flowers and graces over the side of a window box like a waterfall. Dichondra 'Silver Falls' can grow quite long but is easily trimmed back. It can be planted in full to part sun and is heat and drought-tolerant'.

Plant Hardiness Zone: 8-19
Sun exposure: 6 hours or more of direct sun, but can grow in partial sun too.

4. Bacopa (Sutera spp.)

Elegant white blooms with specs of yellow at the center, the Bacopa and its jewel-like blooms are ideas for beds, baskets and container gardening. They can grow up to 4 feet long if its grown in the best conditions and environment.

Sharing her experience with these blooms, Nicole tells us: 'Last year I found a flat of bacopa on the clearance rack of my big box store and had to rescue it. I planted it in my landscape as a ground cover along my sidewalk. I was impressed with its performance in this application and imagine that it would perform similarly in a window box'.

She continues: 'What I liked about bacopa is that it gave me two flushes of flowers. We had flowers in spring and then again in the fall. This added some interest to my garden when other things weren't performing yet or had exhausted themselves with the heat. When many flowers are at their prime the foliage of bacopa framed and supported the rest of my garden nicely'.

Plant Hardiness Zone: 8-11
Sun exposure: Full sun, but can handle a little shade.

5.  Begonia

A much-loved perennial, begonias are a pleasing addition to any garden. These bright colored blossoms come in a variety of hues and there are many types of Begonias that you can chose from. These include: Trailing-Scandent, cane-like, shrub-like, Rhizomatous and Tuberous. Begonia companion planting is also common, for its useful properties.

Nicole says these are great if you have a window box in the shade, 'I'd recommend planting cascading begonias for a foliage plant. Begonias come in every color, a variety of leaf shapes, and flower styles. It's really a diverse group of plants that I am positive you can find one that you like'.

Plant Hardiness Zone: 6-9
Sun exposure: Full sun to shade

6. Sweet potato vines (Ipomoea batatas) 

Typically grown as an annual, sweet potato vines (no they are not edible) are the ornamental version of the infamous sweet potato. With their easy to grow and dynamitic foliage, sweet potato vines are the perfect touch as some of the best flowers for hanging baskets as well as window boxes.

'If you have tall window boxes and want to think outside of the box you could allow a clematis to trail down instead of its usual trellis application. Sweet potato vines are also great for tall boxes that allow them plenty of room to grow,' Nicole explains. 'They can also be trimmed if necessary. Sweet potato vines come in a wide array of colors and shapes. There are heart-shaped, lobed-shaped, chartreuse, deep purple, and even variegated varietals. There is a sweet potato vine that matches any style'.

The plant expert adds: 'They perform beautifully in full sun to part shade and they are not afraid to let you know if they are too dry. So be sure to keep them consistently moist. They will need daily watering during July and August heat'.

Plant Hardiness Zone: 9-11
Sun exposure: 6-8 hours of sunlight

FAQS

 What to consider before choosing cascading flowers 

Before planting cascading flowers, be sure to check your local invasive garden plants list. You can find all the information you need to on United States Department of Agriculture website.

Gardening expert Nicole Dillion says: 'Vines can be quite vigorous. Some of these plants are considered invasive species in certain areas. Check your local invasive species list and exercise caution by keeping them contained within the window box. Do not transfer them to the ground when making seasonal changes without first consulting your local list'.

Maintenance is also key so Nicole advises you take extra care and attention to your window boxes. She add: 'All containers whether a porch planter or a window box require more water than a plant in the ground. Use a good potting mix that will help retain moisture and plan to water every other day at a minimum during the summer. Water at the soil level and avoid watering the leaves. Window boxes are densely planted so airflow can be an issue. Watering at the soil level will avoid any potential fungal development. If this isn't possible, water in the morning so that the leaves have a chance to dry during the day'.

Last but not least, 'replace your potting mix once a year and add a slow-release fertilizer each season to give your plants the best chance to thrive. Instead of tossing the old mix, I use it to top off my raised beds. I inoculate it with well-aged compost and it's ready to plant in again,' Nicole says.

Does the amount of sun or shade matter for cascading flowers?

Yes it does, as it does with most plants.

Nicole tells us: 'the amount of light the plant gets does matter. Most plants listed will thrive in full to part sun, while others cannot handle the rays. Always read the plant label and remember 'right plant right place' to succeed'.

Check out these window box planters