If you want to improve your curb appeal with flower boxes (or just want to look out your window at some pretty plants), these Charleston window boxes are sure to be an inspiration. Learn how to use their design ideas and plant recipes to create gorgeous window box flower combinations for your own home.
Adding window boxes to the front of your home is one of the quickest and easiest ways to improve the curb appeal of your home.
Not to mention giving you something pretty to look at through the window from inside the house as well.
They add a pop of color that can last all summer long if you use the right plants.
And they give you a chance to be creative by trying out new and interesting flower box arrangements every year.
But that’s where a lot of us (myself included) run into a problem.
How do you design window flower boxes so that they look good?
I decided to get some inspiration from one of the cities that has mastered the art of beautiful window boxes: Charleston, South Carolina.
If you haven’t been there, the whole downtown area looks like it stepped out of a picture book with beautiful old houses, well-kept gardens behind wrought iron gates, and real gas-lit lanterns.
And almost every home has drop dead gorgeous window boxes. Even in the middle of the summer!
So what better place to learn how to create beautiful window box flower combinations?
1 | Use Thrillers, Spillers and Fillers
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When it comes right down to it, a lot of these window flower box ideas are using the same Thriller, Spiller and Filler planting formula that I usually use for my containers.
The “Thrillers, Spillers and Fillers” formula is a common way of creating balance in planters of all kinds.
And the Charleston window boxes were definitely using it to their advantage.
Here’s the basic steps of using this formula to put together your window box.
Use Thrillers To Create Height
To start your window box, use large plants to anchor the center of the container and provide a focal point.
Using evergreens is a great way to do this since their needles also provide a contrast in texture with the other plant leaves. And if you live in a moderate climate, they will likely survive through the winter.
Some variegated ivy and bright pink impatiens finish the rest of these really simple window boxes that will flourish in the shade.
Charleston Window Box Plant Combination #1 – Thrillers, Spillers, and Fillers
Best In: Shade
Thrillers: Dwarf evergreen (eg. ‘Green Mountain’ boxwood or ‘Emerald’ arborvitae)
Spillers: Variegated ivy, fuchsia impatiens
Plant Spillers To Add Depth
Planting cascading flowers or greenery that flows over the edge of the window box makes them look much bigger and more dramatic.
These Million Bells Calibrachoa are one of the best cascading flowers for window boxes in the sun.
They are available in pretty much any color you want, and really put on a show!
Just make sure to keep them well watered. They will wilt really fast if they get dried out.
Flower Box Plant Combination #2 – Thrillers, Spillers, and Fillers
Best In: Sun
Spiller: Million Bells Calibrachoa
Fill In The Gaps With Fillers
So far, you’ve seen the Thriller (focal point) and the Spiller (cascading plants), now it’s on to the fillers.
As the name implies, these are the plants that fill out the rest of the box.
They are usually medium-sized plants that add texture or color to the other plants in the container.
I love this whole arrangement so much I had to zoom in closer so you could see all the details.
Window Box Flower Combinations #3 – Thrillers, Spillers, and Fillers
Best In: Sun
Spillers: Evolvulus, Scaevola, Licorice plant
Fillers: Mandevilla, Angelonia
2 | More Is More
The first thing I noticed that was common across all of the Charleston window boxes I saw…they use lots of plants!
Every window box was packed full, and that’s what gives them their full and lush appearance.
Window Box Plant Arrangement #4 – Lots Of Plants
Best In: Sun to Part Sun
Thrillers: Dwarf evergreen (eg. ‘Green Mountain’ boxwood or ‘Emerald’ arborvitae), Caladiums
Fillers: Angelonia, SunPatiens
I think all that foliage also helps to prevent the soil from drying out as quickly (but more on that below).
Charleston Flower Box Recipe #5 – Lots Of Plants
Best In: Part Shade
Thrillers: Caladiums, Coleus
Fillers: Heuchera, Penstemon
Spillers: Creeping Jenny, Million Bells Calibrachoa
3 | Use Layers Of Color
White, Green and Purple
If you’re having trouble figuring out how to design your window box, using layers of color is an easy and effective way to go.
I just love this window box using layers of white, green and purple.
This box starts with white and green Caladium as the focal point, then a layer of purple and green Salvia as the filler, and then a layer of Purple Heart. Finally, a dracaena spike adds some height to the back of the flower box arrangement while the silver Dichondra trails repeats the white all the way to the ground.
Window Box Flower Arrangement #6 – Layers Of Color
Best In: Sun
Thrillers: Dracaena and Caladium
Spillers: Persian Shield and Dichondra
Red, Silver and Green
This one has a layer of green across the bottom and then alternates silver and red across the top.
Window Box Planter #7 – Layers Of Color
Best In: Sun
Thriller: Red New Guinea Impatiens
Spillers: Potato Vine, Ivy and Creeping Jenny
Fillers: Dusty Miller
4 | Repetition Is Key
Window flower boxes really make a statement when they are repeated multiple times.
For a more formal look, duplicate the planting pattern exactly across all of the boxes.
For a more casual look, use the same plants in each of the boxes but not in the exact same spots.
(The plants included in these two flower box arrangements are listed above)
5 | Plant Greenery Under The Boxes
Repeat The Plants From The Window Box
If you don’t have a lot of windows, another flower box idea is to repeat the flowers and plants from the boxes on the ground underneath them. Which makes it look like one big floral display.
This little garden doesn’t take up much space but you certainly can’t miss it when you’re walking by.
Window Box Flower Combination #8 – Plants Under The Window Box
Best In: Sun
Thrillers: Geraniums, Angelonia
Spillers: Scaevola, Vinca
Below The Planter: Boxwood and Coleus, Geraniums, Angelonia, Vinca
Add A Mini Boxwood Hedge
If you have enough less space, adding a miniature boxwood hedge under the window boxes is another way to go.
Caladium and Coleus have multi-colored leaves that make them beautiful statement plants in a container.
These boxes are also using Lobelia which is a great trailing plant with beautiful blue flowers.
Charleston Window Box Plant Combination #9 – Plants Under The Window Box
Best In: Part Shade
Spiller: Trailing Lobelia, Mandevilla
6 | Match The House Color
If you want a no-fail solution to picking flowers for your window box, you can always match your house color.
I think those are faux flowers in the window box of this pink house, but they certainly look pretty.
Similarly, using white flowers against a white house is always a classic color combination which looks stunning with the black trim on this house.
Having the planter box finished in the same color as the shutters and the door also helps to create a cohesive look.
7 | Window Box Ideas For Shade
The streets in downtown Charleston are narrow, the lots are small, and the houses are tall.
All that to say, they have quite a bit of shade. But that doesn’t stop them from having beautiful flower boxes!
You may have noticed that there are actually quite a few window boxes for shade in this list…and here’s a few more…
Blue and White Hydrangeas
Since I love blue and white as a color combination, it’s no surprise that I absolutely love this planter. (It fits right in with these blue and white garden design ideas I found a little while ago).
The great thing about growing plants in containers is that the limited root space keeps them from growing too big.
Which is why planting small bushes like Hydrangeas in a window box is totally fine.
Flower Box Plant Combination #10 – Window Boxes For Shade
Best In: Shade
Thrillers: Blue and white Hydrangeas
Spillers: Creeping Jenny, White and blue Bacopa
Fillers: Maidenhair Ferns
Variegated plants are a staple of shade garden design because the white adds some brightness to a darker area of the yard.
Which is what makes this window box stand out.
All of the leaves are variegated green and white, with just a couple of pansies added for a little pop of color.
When spring is coming to an end and the pansies are past their prime, tt will be easy to swap them out for a summer-blooming cascading annual like Bacopa or Browallia.
Window Box Flower Combination #15 – Window Boxes For Shade
Best In: Shade
Thrillers: Variegated Dracaena
Spillers: Ivy, Pansies
Fillers: ‘Everest’ Sedge grass
For a really easy window box, try using different varieties of the same shade plant.
This box is full of Begonias.
But you can use any shade plant you like.
8 | Window Boxes For Full Sun
When you’re putting together a window box for full sun, be sure to select plants that can survive in hot and dry conditions. Especially if you live in an area that has really warm summers.
Because window boxes aren’t very deep (and there are a lot of plants jammed into that space), they dry out much quicker and heat up a lot more than larger containers do.
So if you want your flower boxes to look good all summer, the plants you select will need to thrive in those conditions.
Which is why a lot of people choose geraniums for their full sun window boxes. They definitely fit that bill.
But then aren’t sure how many geraniums should go in each box or what other flowers to plant with them.
Two Geraniums Per Window Box
This first full sun window box has two geraniums in it. One on either side of a taller Salvia.
The spiky shape of the Salvia contrasts with the rounded shape of the Geraniums to give the box a symmetrical feel.
The rest of the window box is filled in with other sun-hardy plants, like Plumbago, New Guinea Impatiens and Alyssum.
Window Box Plant Arrangement #12 – Window Boxes for Full Sun
Best In: Full Sun
Spillers: Alyssum, Ivy
Fillers: Geraniums, Plumbago, New Guinea Impatiens
One Geranium In A Window Box
This window box flower combination basically reverses the pattern of the last one.
It uses one large Geranium in the middle, and then flanks it on either side with spiky flowers. In this case, white and purple Angelonia.
Which achieves the same effect of adding contrast and interest to more rounded Geranium plant.
You can find the full plant list in plant combination #9 above.
Sun Window Box Without Geraniums
Of course, if you’re not a fan of Geraniums, there are lots of other flower options for full sun window boxes.
This beautiful window box is meant for spring, since the pansies will peter out when it gets too hot.
But with the way they are positioned, the verbena should grow into the gaps, making it an easy transition into a summer flower box when the time comes.
Charleston Window Box Plant Combination #13 – Window Boxes for Full Sun
Best In: Sun
Thriller: Fox Tail Fern
Spillers: Pansies, Verbena
Fillers: Snap dragons, Phlox
9 | Perennial Window Box Ideas
If you don’t want to replant your window box every year, consider filling it with mostly perennials.
Fill In Spaces With Annuals
Most perennials don’t have as long of a bloom season as annuals.
So if you want season-long bloom, create the backbone of your planter with perennials. Then fill in the gaps with annuals.
Make sure to select perennials that are not finicky in your gardening zone. Window boxes are usually colder in the winter and warmer in the summer than other planting mediums. So the plants need to be tough to survive.
It’s also a great idea to include some evergreen plants (like the boxwoods and creeping jenny in the picture above) so you have year-round interest.
Flower Box Plant Combination #14 – Perennial Window Boxes
Best In: Sun
Thrillers: Boxwood, Asparagus Fern
Spillers: Pansies, Alyssum
Fillers: Snap dragons, Phlox (perennial), Poppies (perennial)
Add Foliage Interest
If you don’t want to worry about planting annuals in your perennial flower box, add interest with the foliage instead.
In this window box, a yellow-leaved variety of Heuchera adds contrast to the dark green leaves of the Boxwood and Cyclamen.
And the Sedge grass creates even more interest by adding a difference in leaf texture.
When the Cyclamen is in bloom, it’s an additional pop of color to the window box. But the plant combination shines in the shade even without the blooms.
Flower Box Plant Combination #15 – Perennial Window Boxes
Best In: Shade
Fillers: Heuchera, Sedge grass, Cyclamen
10 | Water The Flower Boxes Automatically
Okay, so this isn’t really a window box design idea, but I think it’s kind of an important step for having beautiful window boxes all summer long.
And I noticed that most of the Charleston houses do this.
They use an automated container watering system like this one*.
If you look closely at the pictures, you’ll see a lot of them have tubes running down the wall. I think that explains how all of their window boxes still look so good in the middle of a hot South Carolina summer!
I set this up for my planters (find out how HERE) and I love it! No more crossing my fingers that it rained enough to keep them alive while I’m away 🙂
Well, that’s it for my window flower box inspiration. Now I’m off to see what I did with those old hay racks I used to have…maybe I can add a little bit of Charleston to my house…
Other Container Planting Ideas You Might Like
- 10 Best Blue Plants For Containers In The Shade
- Patriotic Red, White and Blue Flower Pot Combinations
- How To Make Winter Window Boxes (The Easy Way)
Do you have comments or questions about how to design window box plant combinations (inspired by Charleston window boxes)? Tell us in the section below.
This post was originally published on March 29, 2020 but was updated with new content on November 20, 2021.