12 Stunning Companion Plants For Dahlias

Dahlias are those blooms that steal the show in gardens worldwide; they are the prima donnas of the plant world. Gardeners adore these flowers for their flamboyant petals and vivid colors. 

Despite their showstopping appearance, dahlias are only as good as their supporting cast- and that’s where companion planting comes in. Selecting suitable companions for Dahlias is critical to ensuring they thrive. 

Last year I decided to grow some Dahlias in my garden but needed to figure out what to plant. After some research, I settled on some unassuming companions: Marigolds and Petunias. 

To be honest, I wasn’t expecting much from these humble flowers. 

Surprisingly, the Marigolds kept the pests away while adding a cheerful burst of orange and yellow to my bed. Petunias showcased their delicate pink and white blooms, making a lovely contrast against the bold Dahlias. 

There are some classic combinations to pair with Dahlias, like the standard Roses to the unexpected Salvia. I will share all the stunning companion plants for Dahlias and how you can keep them looking fab.

Choosing Companion Plants For Dahlias 

If you’re considering planting Dahlias, choose the proper companions to hang out with. Just like humans, plants have their preferences regarding their company, and dahlias are no exception. 

You must remember a few things when choosing companion plants for Dahlias.

First, you want to choose plants that have similar growing requirements. You want to avoid introducing a plant that will hog all the nutrients and water, leaving your Dahlias high and dry.

Second, you want to consider color, height, and bloom time.

Choose plants that will complement your Dahlias and not clash with them. Purples and pink look great together, and adding a hint of yellow or orange as a contrast makes them pop even more. 

The benefits of companions are second to none; not only do they look stunning, but they can also help with pest control and soil improvement. 

I once made the mistake of planting sunflowers with my Dahlias; they looked great together. However, the Sunflowers were too tall and blocked the sunlight from my Dahlias.

Choose wisely and keep it simple and compatible; all your plants will be happy. 

Annual Companion Plants For Dahlias

Spice up your Dahlia game with some annual companions. These plants will keep your dahlias company, provide you with a long season of complimentary colors and attract pollinators.

Additionally, annuals are great for filling gaps between Dahlias or adding height to mixed borders.

1. Zinnias 

Zinnias have a classic daisy-like shape and are an annual known for their long-lasting blooms. They make an excellent companion plant for Dahlias because they share similar growing requirements and can complement each other’s colors.

Zinnias come in a color range of bright oranges and yellows to pastel pinks and purples.

  • Planting: Prepare a sunny, well-drained bed with loose soil. You can sow Zinnia seeds directly in the ground after the last frost or start them indoors a few weeks earlier. Space the seeds or seedlings 6-12 inches apart, depending on the variety. Water regularly and fertilize every few weeks with a balanced fertilizer. 
  • Maintenance: Deadhead regularly to promote new blooms. You can also pinch back the tips of the plants when they are young to encourage bushier growth. Water deeply but infrequently, as Zinnias prefer to dry out a bit between waterings. Watch out for any common pests, such as aphids and spider mites, and treat them with insecticidal soap if needed. 

2. Cosmos

Cosmos are delicate daisy-like flowers with ferny foliage, adding a whimsy to your Dahlia bed. They are great for attracting beneficial insects like bees and butterflies.

One reason Cosmos look lovely as a Dahlia companion plant is that they have a similar aesthetic. They can fill gaps between Dahlias or be planted as a backdrop for lower Dahlia varieties. 

  • Planting: Cosmos requires a sunny, well-drained spot and can be started indoors by seed a few weeks before the last frost. If you plant them directly in the ground space, the seeds are 12-18 inches apart. Apply a balanced fertilizer every few weeks and water them regularly to keep them looking fresh. 
  • Maintenance: Remove any spent flowers to encourage more blossoms and pinch the tips of the plants when they are young to encourage bushy growth. Avoid over-watering and watch for pests like aphids and spider mites. Treat pests with an insecticidal soap spray or neem oil solution. 
Also read  15 Wonderful Self-Sowing Annuals (With Photos)

3. Marigolds 

Marigolds are a hardy plant as a companion for Dahlias; they have sturdy stems and bright, cheerful blooms to add some extra oomph to your garden. Their scent can help to repel pests like mosquitoes and aphids.

Marigolds grow to a height of 6-24 inches, making them an excellent choice for planting in front of dahlias which can grow quite tall. 

  • Planting: Plant Marigolds in a bright sunny spot in the garden with well-draining soil free from debris. Marigolds aren’t fussy with soil, but if you add some extra compost or well-rotted manure to the native soil, they will flourish. When the soil has warmed up, transplant seedlings outdoors or after the last frost or sow seeds 6-12 inches apart. 
  • Maintenance: Water deeply when the soil is dry to the touch, and be careful not to overwater to prevent root rot. Fertilizing is unnecessary, but if you want to give them an extra boost, you can add a slow-release fertilizer at the beginning of the growing season. Remove spent flowers to prolong the blooming period, and you can even use the flowers for garnishing your favorite dishes.  

Perennial Companion Plants For Dahlias

Perennials are an excellent choice for a steady stream of blooms throughout the growing season.

By planting perennials alongside Dahlias, you can create an active display of continuous color and texture from spring to fall.

4. Salvia 

Salvia is an excellent perennial choice as a companion plant for Dahlias, as their tall spikes of blue, purple, or red flowers add serious drama to your Dahlia bed.

Salvia produces long-lasting blooms, which are great for providing nectar to pollinators to your garden bees.

  • Planting: Salivas prefer full sun; prepare an area with well-draining soil that receives 6 hours of direct sun daily. Dig a hole twice the size of the rootball and place the seedling in it. Backfill the hole and water the well.
  • Maintenance: Water newly planted Salvias deeply and regularly until they are established. Once established, they are drought-tolerant and require occasional watering. Fertilize once or twice during the growing season with a balanced fertilizer. Prune back Salvias when they have finished blooming in the fall to prevent them from becoming leggy. 

5. Veronica

Veronicas range in height from low growing to tall upright plants, which can add structure and contrast to your Dahlia bed.

With shades of blue, purple, and white flowers that bloom from late spring to early fall, they will extend the blooming season in your garden and provide a continuous source of nectar for pollinators. 

  • Planting: Choose a location that gets 6 hours of full sun per day. Ensure the soil drains water well, and then plant in a hole twice the size of the root ball. Make sure the root ball is level with the soil surface. 
  • Maintenance: Regular watering is needed for newly planted Veronicas; once they have matured, they can become more tolerant to dry conditions. Fertilize once a month during the spring and summer using a balanced fertilizer. Prune them back in the fall after they have finished blooming to promote bushier growth.

6. Coneflowers 

Commonly known as Echinacea, these tall upright plants come in shades of pink, purple, orange, and white, complementing dahlias’ colors.

Coneflowers typically bloom from midsummer to early fall and are a low-maintenance option to add to your Dahlia display.

  • Planting: Plant in the spring after the last frost in a full sun position. They can tolerate part shade but may grow slower. Ensure the soil drains well and is free from any debris. You can add some compost to native soil to give it a boost. 
  • Maintenance: Deadhead the Coneflowers regularly to encourage new blooms and prevent the plant from becoming leggy. Cut back the stems to about 6 inches above the ground in the fall to prepare for winter. Use a balanced granulated slow-release fertilizer at the beginning of the growing season to keep them thriving. 
Also read  12 Full Sun Annuals (That Bloom All Summer)

Bulb Companion Plants For Dahlias

Bulbs and Dahlias are like a match made in heaven. Dahlias have a shallow root system, whereas bulbs can grow deep into the soil providing support and nutrients to the Dahlia roots.

This symbiotic relationship results in a stunning display of colorful blooms varying in texture and scent. 

7. Gladiolus

Gladiolus is an excellent companion for Dahlias as they come in various heights and colors.

The vibrant reds, pink, purple, white, and yellow sword-like flowers make striking cut flower arrangements when combined with Dahlias. You can select colors that will contrast with Dahlilas or complement them.

Gladiolus has a long blooming period and grows tall, so it may need to be supported with a stake. 

  • Planting: Plant bulbs in the spring when the ground is workable. Dig a hole twice the size of the corm (bulb-like structure), and ensure the pointed end faces up. Ensure the soil is well draining and free from any rocks or debris. Cover the hole and water well. Ensure you choose a location that receives direct sun for at least 6 hours daily and will not obstruct the light from other plants. 
  • Maintenance: Water regularly, especially during periods of drought. Fertilize with a balanced fertilizer once a month. Provide a stake to prevent them from falling over in high winds or heavy rains. When the bottom two or three flowers on the gladiolus spike have opened, it’s time to harvest the whole spike. Cut the stem at an angle and remove any leaves below the water level in your vase. 

8. Lilies

Lillies can add sweet fragrance and charm to your Dahlia bed.

The pink, white, orange, and yellow flowers open mid-summer to fall and range in height from small plants to tall upright plants adding dimension and contrast. 

  • Planting: Plant Lily bulbs in the fall or early spring, depending on your climate. Dig a hole in well-draining soil in full sun to part shade spot. Ensure the hole is 2-3 times the bulb’s height, and place the bulb with the pointed end facing up. Cover the hole and water thoroughly. 
  • Maintenance: Add a layer of mulch to help conserve moisture and prevent weeds from growing. Water frequently and deeply to supplement rainfall. Once the flowers have finished blooming, cut off the spent flower heads to prevent the plant from using energy to produce seeds, and fertilize once a month during the growing season with a balanced fertilizer. 

9. Alliums

Alliums bloom a round ball-like flower head in shades of purple, pink, or white and will make your Dahlia bed look like a million bucks.

They are great for repelling pests like deer and rabbits, and the flowers are edible, too, making them great for garnishing your dishes. 

  • Planting: Plant in the fall, around 4-6 weeks before the ground freezes. Choose a sunny spot with soil that drains well. Plant the bulbs pointy side up about 2-3 times the depth of the bulb itself. If your soil is heavy, add some sand or compost to improve drainage. 
  • Maintenance: Keep Alliums moist but not soggy. Water them once weekly or more often if the weather is hot and dry. Give them a boost of fertilizer by adding compost or a balanced fertilizer in the spring. Cut back the foliage once it turns yellow and starts to die back. Remove any spent flowers to encourage more blooms. 
Also read  5 Fun Landscaping Ideas Around Trees

Foliage Companion Plants For Dahlias

Foliage plants provide a lush green backdrop that accentuates the vibrant blooms of Dahlias, adding texture and variety.

Use foliage plants to fill in the gaps between Dahlias, and watch as you create a cohesive garden that flourishes year after year. 

10. Ferns

Ferns and Dahlias are the perfect pair! While Dahlias steal the show with their vibrant blooms, ferns provide a beautiful lacy textured backdrop with their delicate fronds.

Ferns prefer the same growing conditions as Dahlias making them the perfect companion with low maintenance.

  • Planting: Plant in spring or fall in a location with partial sun to full shade for at least 4 hours daily. Ensure the soil drains well and the hole is slightly larger than the root system. Ensure any tall Ferns don’t obstruct the sun from any nearby plants.
  • Maintenance: Water regularly to keep the soil consistently moist. A small amount of fertilizer in the spring will give them an extra boost. Add a layer of mulch to the base of the plant to prevent weed growth and retain moisture. Remove any dead or damaged fronds from Ferns as needed to keep them looking tidy. 

11. Hosta

Hosta has broad, lush leaves that can create a dramatic contrast with the more delicate foliage of Dahlias.

They come in shades of green-blue and variegated patterns, adding depth to your Dahlia display. 

  • Planting: Choose a spot with 4 hours of indirect sunlight daily. Plant Hostas in spring or fall in well-draining soil. Add compost or organic matter to provide extra nutrients. Avoid over-watering to prevent root rot. 
  • Maintenance: Use a balanced fertilizer monthly in the spring and summer. Avoid fertilizing during the winter when the plant naturally slows down. Remove any dead or damaged leaves and provide a layer of organic mulch to keep the moisture in the soil. 

12. Heucheras

Also known as Coral bells, these plants have small delicate leaves that perfectly contrast with Dahlias’ bold, dramatic foliage.

This low-growing plant comes in shades of greens, purples, and pinks, and when planted in the foreground of Dahlias, they can add an extra feature to your bed. 

  • Planting: Plant from seedlings in spring or fall in a part shade spot. Use soil that is light and drains well. Make a hole that is a bit larger than the root system and place the seedling in it. Ensure it has enough space around the base of the plant. Keep the soil moist and water deeply and regularly. 
  • Maintenance: Use a balanced fertilizer like 10-10-10 NPK in the spring and summer. Mulch to the base of the plant with organic material to help conserve moisture. Prune any damaged or dead leaves to keep them looking lush and tidy.

The Perfect Partners: The Best Companion Plants For Dahlias Revealed 

Selecting the perfect companion plants for Dahlias can make all the difference in your garden. Companion plants can add diversity to your Dahlia display while offering a range of benefits, from pest control to improved soil.

Feel free to get creative with your companion planting choices. Mix and match annuals, perennials, bulbs, and foliage plants to create a dynamic Dahlia bed.

Choosing the perfect partners for Dahlias is about creating a beautiful and diverse garden that reflects your unique personality and style. So go ahead and try it. I’m sure your friends will be green with envy! 

Lucy Young

Meet Lucy, a seasoned gardener with a green thumb and a wealth of experience cultivated over 10 years in her own backyard oasis. Now, she channels her passion into writing, sharing invaluable gardening knowledge on her website. From nurturing plants to expert pruning techniques, Lucy's articles are a treasure trove for both seasoned enthusiasts and budding gardeners. Join her on this leafy journey as she sprinkles insights, tips, and tricks to help you create your own flourishing paradise. Get ready to dig into her gardening wisdom and unlock the secrets of a thriving garden!

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