6 Bright, Colorful Annuals You Can Plant in Container Gardens This Month
It’s finally the dog days of summer! By now, you’ve spent plenty of time nursing your container garden by way of trimming, watering and patrolling for pests—and your small space has rewarded you with a beautiful bounty of blooms and foliage. But you might have noticed that a few annuals—plants that live for just one season, and do not return year after year—have petered out over the past couple of months. The sad truth is, sometimes those cute 4-inch pots of color just don’t last the entire summer and need to be replaced. That’s totally normal! Oftentimes you’ll find that other plants that are living alongside them will expand to cover the gaps, but most of the time you should simply pop new plants into the empty spaces.
Colorful annuals are a great way to refresh a container garden at any point during the year—but this is particularly true in late summer, when bright pops of color can help bring definition and structure to your outdoor space. These one-season plants come in all different shapes and sizes, from mounding blooms to cascading foliage. Best part? This time of year you’ll be able to find annuals marked down at your local nurseries—and who doesn’t love a good plant deal?
Whether you’re looking to refresh your existing container garden or to plant up a forgotten pot, this list of colorful annuals—all available in the late summer season—will help you on your way.
Angelonia (Angelonia angustifolia)
I am a recent convert of Angelonia in container gardening. Up until this year I had admired these upright, colorful annuals from the greenhouse floor and only purchased them for my small bedding garden. This year, however, I purchased them for a container and realized that this plant is perfect for containers—and that I will be buying it every year from now on.
Angelonia thrives in hot, full sun conditions and is available in shades of mauve, white, pink, purple and blue. The mauve is my favorite as it brings a subtle yet defined pop of color. This plant grows upright with flowering spikes, so it’s the ideal backbone for any container design. These blooms love the sun but they also need to be watered when the soil becomes dry; at this point in the summer, that will be almost every day in a container. To promote new growth, cut back any dead flower stalks. Bonus: For anyone who lives in a zone with little to no frost, you will be able to grow this plant as a perennial.
Cockscomb (Celosia)
Celosia, also known as Cockscomb or Cock’s comb, is a gorgeous annual that comes in all different shades of color from neon fuchsia to burnt orange to pale pink. There are also three different bloom types, including plumed, crested and spiked. Each brings its own flair to container gardening. If you’re worried about celosia taking over your containers, try a dwarf variety. Celosia argentea is the perfect option for containers as it only grows to about 10 inches high compared to the 30 inches of the typical celosia varieties. Celosia plants love full sun and consistent watering.
If you’re feeling crafty, cut a few celosia blooms and hang them to dry. These flowers preserve perfectly with their vibrant color intact.
Marigolds
Ah, marigolds. Many people favor this plant, but just as many people cannot stand them because of their peculiar scent. Whatever side of the fence you’re on, you cannot deny that these annuals bring big color to container gardens. A particular favorite for butterflies because of the bright colors, marigolds will continue to bloom until fall’s killing frost arrives. These plants will thrive in full sun to partial shade and must be deadheaded by plucking off spent flowers to promote new blooms.
Marigolds are great annuals to use along the front edge of a container design as many varieties don’t grow more than a few inches tall throughout the season. To ensure petite size, try a French variety like “Scarlet Sophie” or “Gypsy Sunshine.”
One of the best things about marigolds is that they are naturally pest-resistant and will keep those nasty bugs away from your containers. If you live in a suburban or rural area, you’ll be happy to learn these are also deer resistant. Note that the toxins found in marigolds have very little effect on humans (and can be found in many culinary dishes), but are considered toxic to dogs and cats.
Petunias
What kind of annual-lover would I be if I didn’t bring up this favorite old standard? Petunias are one of the best-selling annuals in the country because of their hardiness as well as their sheer variety of colors. They’re wonderful in hanging baskets as well as stationary containers, since they’ll very stylishly drape over the edges. They’ll also provide blockbuster color all season long, provided they are deadheaded and given enough water.
Petunias will thrive in full sunlight to partial shade and will produce plentiful blooms until fall’s frost. There are hundreds of varieties out there, but a few of the most mind-blowing are “Limelight,” “Fortunia Early Blue Vien,” and “Wave Blue.”
Petunias are prone to pests like aphids and mites, so keep your insecticidal soap handy.
Coleus
While there are all kinds of varieties of coleus that thrive in full-shade to full-sun conditions, these plants have become the darling of shade gardens. There are many varieties that provide blasts of color while living in the darker corners of your outdoor space. While coleus plants aren’t known for their blooms, they are renowned for big, lush foliage and easy care.
Varieties like “Limetime,” “Watermelon,” and “Alabama” are some of my favorites, but there are many more out there. Coleus is a great companion plant to other shade-lovers like heuchera, Solomon’s seal and impatiens.
Keep a lookout for faded colors on the leaves—this means that your plant is getting too much sun. If you’re feeling adventurous, try planting a container using only different varieties of coleus! The effects are stunning. Keep in mind that while coleus is non-toxic to humans, it is considered toxic to dogs and cats.
Verbena bonariensis “Buenos Aires”
I don’t want to play favorites here, but this specific variety of verbena is easily in my top five list of annuals. The “Buenos Aires” variety of Verbena bonariensis promotes a very specific aesthetic. This plant grows tall, spindly, and wild—which checks all the necessary boxes for my container gardens. The purple blooms attract pollinators like bees and butterflies, which is an added bonus.
If tall and spindly isn’t your thing, try the “Rigid” variety for a lower growth pattern.
Verbena is a sun-loving plant and is also quite drought tolerant. It is also a must-have if you’re growing a cutting garden in your container. Plant it in the back of your container and use it as the backbone of your design. If you live in light- or no-frost areas, you might be able to grow this plant as a perennial.