Complement The Dahlia Flowers In Your Garden With These 12 Beautiful Companion Plants

There are lots of great reasons to plant dahlias, including the sheer diversity of color afforded by their many varieties and the bevy of beautiful blooms that last from late summer to fall. You can also grow dahlias to attract beautiful hummingbirds and other pollinators, like bees and butterflies. These flowers require some loving care to keep them blooming at their best, including finding the right sunny spot with soil that drains well. However, the reward is well worth the effort when dahlias put on their colorful display. Most gardeners prefer a little diversity in their lives, though, and if you do, you may be wondering what to plant alongside the dahlias.

When it comes to picking the right companion plants, there are a few you should shun. For instance, dahlias and sunflowers are not a good match in the garden and nearby trees may provide too much shade for them. Choosing plants that have similar growing requirements is a good idea; others can serve as trap crops to keep pests like aphids and Japanese beetles away. Need some specifics? We have 12 different dahlia companion plants for you to consider.

Snapdragons (Antirrhinum majus) require a growing environment that's similar to dahlias', which makes this plant a logical perennial companion in zones 7 to 10. Also grown as annuals, snapdragons put on showy flowers in a variety of colors, including purple, yellow, pink, white, and orange. They grow about 6 to 10 inches across and reach 6 inches to 3 feet in height. The flowers look amazing in cut flower bouquets and attract butterflies and hummingbirds when left in the garden. And while you might worry about deer eating your dahlias, they don't usually munch on this plant.

Nasturtium (Tropaeolum majus) is an easy-to-grow perennial in zones 9 through 11, and an excellent plant to grow alongside dahlias. The flowers on these plants vary in hue from orange and yellow to red and cream. Their blooms pop against bright green foliage that looks similar to water lily leaves. Since nasturtiums are known to attract aphids, some gardeners plant them to divert the pests from their dahlias. However, nasturtium grows aggressively and is considered invasive in some parts of Coastal California and Hawaii, so check with your local extension office before planting. 

Geranium (Pelargonium) is another plant you can add to the garden to lure pests, since it will draw Japanese beetles away from the dahlias. In zones 10 to 11, you can grow geraniums as tender perennials and as annuals in colder regions. They grow to about 2 feet in height and about as wide, producing large clusters of colorful blooms. Geraniums thrive with at least 6 hours of direct sun each day. Geraniums can be poisonous to pets, but the symptoms are not severe. They may also cause skin irritation in humans. The condition is generally minor but is still worth noting.

Cut leaf Cosmos (Cosmos bipinnatus), also called Mexican aster, is an easy-to-grow hardy annual that's well-suited for growing alongside dahlias in warm climates. These plants tolerate the heat of full sun and do well in dry soil conditions. To encourage abundant blooms, avoid overwatering them. These plants grow up to 4 feet tall and put on flowers with yellow centers surrounded by white, pink, or red petals. They bloom from June through to the first frost, so their flowers will emerge prior to dahlias' then match their blooming bounty through the remainder of summer and into fall.

Sweet alyssum (Lobularia maritima) most often produces profuse clusters of white flowers, but many cultivars have also been developed from the rarer pink and purple varieties — all of which can compliment your dahlias. This annual grows in zones 5 to 9 and reaches heights of 3 to 9 inches. Sweet alyssum likes full sun when planted in areas with cooler weather, and more shade in warmer regions. Regardless of the climate, sweet alyssum needs soil that's moderately moist and has good drainage. Regular deadheading is recommended to keep these beauties blooming. Don't over-fertilize this one, however, or you'll get more foliage and fewer blooms.

Sea lavender (Limonium latifolium) is a herbaceous perennial that puts on pretty purple, blue, or pink spiky flowers that look lovely with dahlias in mid- to late-summer cut flower arrangements — and in the garden. Before it blooms, this plant forms dark green leaves that can serve as nice ground cover. Hardy in zones 4 through 9 and some parts of zone 3. Sea lavender needs good drainage and can tolerate dry soil. This one thrives in full sun, but afternoon shade is best in very warm climates. As the name implies, this plant can live in areas with exposure to salt,and, as a bonus, it's deer-resistant. 

The daylily (Hemerocallis) is a favorite among gardeners growing perennials and thrives in zones 3 to 9. The botanical name translates to "beautiful for a day" in Greek, in fact, aptly indicating that the blooms aren't long-lasting, even though they are quite attractive. There are, amazingly, more than 100,000 different cultivars of the daylily, and their blooms range in size from 2 inches to more than a foot in diameter. Colors include traditional orange and yellow along with a variety of other hues except for exact white and blue, so you can easily find an option to complement your beloved dahlias.

If you want to let your dahlias take center stage in your garden, a border plant like lady's mantle (Alchemilla mollis) might be the companion plant you've been seeking. With large leaves that measure as wide as half a foot and small yellow flowers, this plant can produce seeds aggressively and cover lots of ground. You can divide its clumps each spring. Lady's mantle is hardy in zones 3 through 8 and is viewed as easy to care for, although its leaves may burn when exposed to too much sun in hot regions.

Peonies (Paeonia sp.) bloom in the springtime, but their shiny green leaves can make the dahlias' colorful petals pop while they're flowering from summer until the first frost of fall. These perennial shrubs grow from 2 ½ to 3 feet tall and about as wide in zones 3 to 8. Peonies are available in several varieties that offer white, pink, and red blooms. Like dahlias, they prefer areas with sun and soil that drains well. They'll thrive and bloom their best if you leave them in the same spot for the long haul.

As an alternative to a shrub or another type of flowering plant, you can select an ornamental grass like fountain grass (Pennisetum alopecuroides) to plant behind the dahlias in your garden. Cultivars of this plant are hardy in zones 4 to 10 and can grow from 1 to 4 feet tall. With bowing stems and spiky blooms, the shape of this ornamental grass does indeed resemble a fountain spouting water. The foliage color will change to a bronzy hue in the fall and becomes beige during the wintertime, although the shape remains basically the same.

Yarrow (Achillea) has many other names including bloodwart, devil's nettle, and stenchgrass. This genus of blooming plants belongs to the aster family (Asteraceae). Like dahlias, they do well in full sun and soil that affords good drainage. Yarrow blooms range from pink and orange to red, yellow, and white. Deadheading the flat-topped flowers will encourage more blooms and keep seed spread to a minimum as yarrow's growth can be aggressive when left unchecked. They make good border plants growing 1 to 4 feet in height and can be a great garden addition to attract butterflies.

While your first thought might not turn to tulips (Tulipa) when it comes to dahlia companions, they are a viable choice. Like dahlias, they grow best in full sun and soil that drains well. They come in many different types and some bloom earlier than others, but always in the springtime, so they'll have faded by the time the dahlias start to put on their own colorful show. If you enjoy keeping a cutting garden, you can count on flowers for your vases from spring through fall by planting both tulips and dahlias.