Adding cascading window boxes to your home is an easy way to increase curb appeal and inject stunning color around your home’s windows. The spilling blooms and trailing foliage in this type of container garden create a beautiful framed effect that livens up any facade. When choosing plants to plant in your window box, go for spillers or trailing plants with long, spreading stems that will gracefully spill over the edges of hanging baskets and window boxes.
In our guide, you can learn more about popular annuals like petunias, Lobelia, and verbena that bloom prolifically while trailing gracefully from containers.
By the end, you’ll better understand how combining cascaders like sweet potato vine and creeping Jenny with upright flowering plants like zinnias and trailing snapdragon look best. It will also create a professional look to your window box and provide an increase in overall curb appeal without spending a lot. When choosing cascading flowers and plants for your window boxes, go for ones that spill gracefully out of the box. (Read Weed Killer That Won’t Kill Roses)
Top 10 Best Flowers for Window Boxes
The first of our window box flowers is Ivy, a classic perfect for window boxes. English ivy (Hedera helix) is an excellent option as it grows well in morning sun or shade and trails 5-10 feet long.
The glossy green foliage provides the perfect backdrop to showcase colorful flowers. Ivy comes in many varieties, like variegated ivy, adding pretty contrast with white splashes on the leaves. Ivy grows quickly to spill out of the box and trail far below.
Sweet Potato Vine
For gorgeous cascading foliage, fill your window box with sweet potato vine. These flowers grow best in window boxes; the trailing stems grow up to 3 feet long and beautifully spill over the edges.
Sweet potato vine comes in various leaf colors like burgundy, variegated green and white, and bright lime green. It provides a lovely curtain of foliage and works well mixed with flowers. Easy to grow, it’s a perfect choice for window boxes to create a flowing effect.
No list of cascading flowers is complete without petunias. These popular annuals grow 6-12 inches tall but spread 3 feet wide thanks to their profuse trailing stems. Petunias’ bell-like flowers bloom in spring, summer and fall in bright pink flowers, purple, red, yellow, or white.
Wave petunias are an excellent cascading variety, while Surfinia petunias feature delicate small flowers on long hanging stems. Use petunias as cascading spillers combined with upright plants.
Also called lemon bacopa, this pretty annual has tiny white flowers and small rounded leaves on trailing stems that grow up to 36 inches long. The flowers bloom steadily all season if deadheaded. Bacopa thrives in full sun exposure, so keep your soil moist in your flower bed. (Learn How Long Can Flowers Live Without Water)
Thanks to their beautiful cascading habit, impatiens are hugely popular for window boxes and containers. Busy Lizzie impatiens produce an abundance of flower heads around the plants in shades like white, pink, red, purple, and coral throughout the summer. The 8-inch tall plants and flowers spread up to 20 inches wide from the profusion of their trailing stems. Impatiens do best in shade and will attract hummingbirds to your garden.
A delicate-looking plant, Lobelia bears hundreds of tiny flowers on trailing stems from summer to fall. Excellent for window boxes and hanging baskets, the 6-inch tall plants have a spread of up to 2 feet. Lobelia comes in shades like blue flowers or white, purple, and shades of pink. Make sure Lobelia gets afternoon sun and shade in hot climates.
Million bells, called calibrachoa, are tender perennials that function as fast-growing annuals in the garden. Their trailing stems spread up to 2 feet and will elegantly spill from window boxes and containers. The prolific blooms resemble petite petunias in pink, purple, yellow, white, red, and bicolor shades. Million bells require full sun for flowers that look the best. These easy-to-maintain plants will flower continuously in your window boxes.
The leaves and flowers of nasturtiums are edible, making them a great cascading plant for kitchen window boxes. Trailing up to 6 feet long, nasturtium stems will gracefully spill from window boxes with bright, colorful blooms in orange, red, yellow, peach, and mahogany shades.
Alyssum is one of the best annuals for cascading over window boxes with masses of tiny flowers. Alyssum grows just 4-6 inches tall and spreads 1-2 feet wide thanks to its trailing habit. The dainty flowers come in white, pink, and purple colors and bloom from spring to fall.
For beautiful two-tone flowers trailing from your window boxes, look for cascading fuchsia. The vibrant blossoms feature a burst of “petals” in shades like fuchsia, red, purple, and white with contrasting centers. Trailing 1-3 feet long, cascading fuchsia varieties will elegantly spill over window boxes. Provide some afternoon shade in hot climates.
Verbena is a popular annual loved for its clusters of small flowers and trailing habit. Excellent in window boxes and hanging baskets, verbena has a spread of up to 3 feet. Flowers look brilliant with colors like red, pink, purple, white, and blue from spring to late fall.
Give verbena full sun and well-drained soil. Let this tough plant trail from your window boxes when packed with plants when you want flowers nonstop. (Read Weeds That Look Like Flowers)
Also known as moneywort, creeping Jenny (Lysimachia nummularia) is a low-growing perennial grown as a groundcover. However, it also makes an attractive trailing plant that trails over the sides of your window box, with its round leaves and fast spreading stems. Creeping Jenny grows 2-4 inches tall but sends out 2-foot-long trailing stems.
Sweet violets (Viola odorata) produce hundreds of blooms in shades of purple, blue, yellow, and white during spring and fall. The low 1-4 inch tall plants spread 6-12 inches wide via trailing stems and look stunning cascading out of window boxes. The edible flowers and heart-shaped leaves add delightful texture and color. Grow violets in partial shade for optimal flowering over the edge of your window box.
Trailing thyme makes an excellent cascading plant for window boxes with the delicious benefit of being able to harvest it for cooking. Thyme produces little lavender, pink or white flowers on pretty trailing stems up to 18 inches long.
For a cascading plant with gorgeous silver foliage, try dichondra. This perennial grows just 2-4 inches tall but sends out stems up to 3 feet long that will trail gracefully from window boxes and hang like silver curtains.
Also called summer snapdragon, angelonia produces spikes of flowers reminiscent of snapdragons on trailing stems up to 14 inches long. The long flower spikes contrast beautifully with the lush green foliage. Angelonia loves heat and thrives in full sun and average soil. Use it as an annual in window boxes and containers.
The delicate 2-inch daisy-like blooms of the fan flower give it an airy, fern-like appearance as the flowers dangle on slender 8-inch trailing stems. Blooms appear in shades of purple, yellow, white, pink, and blue from early summer to fall. Plant fan flowers in window boxes in full sun to partial shade and let them gracefully spill over the edges.
Also known as parrot’s beak, the lotus vine produces beautifully unusual flowers that resemble parrot beaks on trailing stems up to 3 feet long. Give lotus vine full sun to partial shade and average moisture.
For a blizzard of tiny white flowers trailing from your window boxes, grow sweet alyssum. The petite blooms completely cover the 6-inch tall plants. Although short, sweet alyssum makes an excellent spiller for window boxes and hanging baskets. Plant it in full sun or part shade and average soil.
Morning Glory (Ipomoea tricolor) produces lush green heart-shaped foliage on long vines around 10 feet, making it ideal for cascading from window boxes and trellises. Provide morning glory, full sun, partial shade, and moist, fertile soil. (Learn How To Clean Dusty Fake Plants)
Achieve Gorgeous Cascading Window Boxes
Now that you know some of the best cascading plants for window boxes, it’s time to get designing! Combining trailing plants with some upright ones will give you beautifully draping and balanced window boxes bursting with flowers and foliage.
Choose the Right Plants
- Select both cascading and upright plants to create contrast and visual interest. Go for trailing plants like ivy, petunias, and sweet potato vine mixed with taller flowers, herbs, or ornamental plants.
- For shaded window boxes, pick shade-loving trailing plants like ivy, impatiens, Lobelia, and dichondra mixed with shade perennials.
- Trailing plants like sweet potato vine, verbena, petunias, and million bells combined with sun-loving flowers like marigolds, zinnias, and cosmos will thrive for full sun window boxes.
Maximize the Cascading Impact
- Plant cascading plants like ivy, sweet potato vine, and fuchsia near the edges of the box so they can spill over the sides most dramatically.
- Use upright plants in the middle and back of the box to provide height and contrast to the spillers.
- For the fullest effect, plant cascading annuals densely, with at least 20 plants in a typical window box.
FAQs About Cascading Plants for Window Boxes
What are some good cascading flowers for a sunny window box?
Some excellent cascading flowers for full sun window boxes include petunias, million bells, verbena, nasturtiums, Lobelia, sweet potato vine, and ivy.
Should I fertilize my window box plants?
Feed window box plants with a balanced liquid fertilizer every 2-4 weeks during spring through fall to encourage lush growth and prolific blooms.
How much sun do window boxes need per day?
Most window box plants need at least 4-6 hours of sun daily.