Dahlias are easy to grow and bring life to your garden. They have bright colors, are strong, and can flower until the first frost. Dahlias like well-balanced and composted soil, and full sun. With 42 different species and thousands of cultivars, dahlias offer plenty of variety. Variations in color, flower form, size, and foliage make it easy to find one youll love.
Generally winter hardy in zones 7-10, and tubers can stay in the ground. In places that get cold, tubers can be dug up, stored for the winter, and then planted again in the spring, after there is no longer any risk of frost. (See below for storage tips. ).
It can be anywhere from 1 to 6 feet tall and 1 to 3 feet wide, depending on the type. Border dahlias are 15 to 20 inches tall.
According to Frances Palmer, well-known potter and dahlia enthusiast, a good planting time for tubers is May. Here are her recommendations for planting:
You can start tubers inside for 6 weeks before moving them to the garden if you live in a cold area and want to get a head start. Plant them in pots with potting soil and provide plenty of light and water. When the ground temperature in your garden reaches 60°F it is safe to transplant your dahlias.
With their vibrant colors and bountiful blooms, dahlias are garden superstars. These easy-to-grow tubers come in a dazzling array of flower shapes, sizes and hues, ensuring there’s a dahlia for every garden.
When thoughtfully designed, a dahlia garden can provide non-stop color and visual impact from midsummer until fall frost. The key is combining varieties and companion plants in creative ways tailored to your space.
In this article, we’ll explore 12 stunning dahlia garden design ideas to inspire your own landscape. With proper planning and plant pairing, your dahlia display can be the talk of the neighborhood!
12 Beautiful Ways to Design a Dahlia Garden
Here are a dozen eye-catching approaches for using dahlias in gardens and containers
1. Dahlia Cutting Garden
Grow dahlias en masse in a dedicated cutting patch. Choose prolific bloomers on sturdy stems in a range of heights and colors for variety. Underplant with cool foliage like coleus or sweet alyssum.
2. Low-Growing Border
Edging a walk or border with dwarf and miniature dahlia varieties creates colorful curb appeal. Try the dark-leaved ‘Myrtles Delight’ and bicolored ‘Gallery Art Deco’.
3. Mixed Perennial Beds
Blend mid-size and tall dahlias with perennials like coneflowers, asters and grasses. Repeat colors for harmony and contrast forms for interest.
4. Dahlia Hedge
Plant a row of dwarf dahlias like ‘Copper King’ or ‘Bed Head’ along a fence or property line for a vibrant dwarf hedge. They’ll bloom profusely at a manageable size.
5. Dahlia & Annual Combinations
Team dahlias with fast-growing annuals like zinnias, marigolds or cosmos for nonstop flowers. Choose annuals in dahlia-complementing colors.
6. Above-Ground Containers
For stunning stand-alone splashes of color, plant container dahlias like ‘Mystic Illusion’ in colorful pots on patios or in entryways.
7. In-Ground Containers
Sink pots flush with soil and fill with dahlias for a polished, modern look. Go monochromatic or color block with pots and blooms.
8. Geometric Dahlia Beds
Plant identical dahlias in rectilinear or triangular beds outlined in stone or metal edging. The bold geometry showcases the flowers.
9. Dahlias as Specimen Plants
Let unique varieties like ‘Sassenfrass’ or dinnerplate types steal the show. Surround them with low grasses or groundcover.
10. Succulent-Dahlia Combinations
Contrast dahlia flowers and foliage with fleshy succulents like Echeveria and Aeonium. Purple and chartreuse pair well.
11. Supporting Cast for Roses
Underplant rose bushes with low-growing dahlias in similar hues. They’ll cover bare rose stems and echo the colors.
12. Dappled Shade Plantings
Partially shaded gardens allow you to grow dahlias where they wouldn’t thrive in full sun. Mix with impatiens or coleus.
Design Tips for a Show-Stopping Dahlia Garden
Follow these tips for designing a dahlia display with maximum visual appeal:
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Combine heights and flower types for multi-layered interest.
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Mass plantings have high impact. Repeat varieties in drifts.
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Use neutral greens like parsley or artemisia to make blooms pop.
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Weave climbing vines through supports to backdrop dahlias.
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Contrast spiky flowers with rounded foliage like hostas.
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Plant in clearly defined beds or rows for bold structure.
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Edge beds with bricks, stone or clipped herbs for polish.
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Pair with classic garden embellishments like obelisks or urns.
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Save dahlias for late-season color after early perennials fade.
With smart pairings and creative layouts, your dahlias can take center stage and shine as the star of your garden.
Complementary Plants for Dahlias
Beyond using dahlias together, combining them with other plants that have complementary form, texture and color creates a cohesive landscape. Here are some excellent dahlia companions:
Flowers: Zinnias, marigolds, asters, coneflowers, cosmos, snapdragons, salvias
Foliage: Parsley, fennel, artemisia, coleus, hostas, grasses
Vines: Morning glories, hyacinth bean, cup and saucer vine, climbing nasturtiums
Shrubs: Spirea, potentilla, buckthorn
Caring for Dahlias Through the Seasons
To keep your dahlia garden looking its best, follow these seasonal care tips:
Spring: Plant tubers or potted dahlias after the last frost when soil is warm. Provide support with stakes or cages. Pinch emerging shoots to encourage bushiness.
Summer: Water during dry periods, especially at bloom time. Deadhead spent flowers to promote more blooms. Stake tall varieties as needed. Watch for pests like earwigs, slugs and Japanese beetles.
Fall: Dig up tubers after first hard frost. Cut back stems, allow to dry and store tubers in a cool place for winter. Apply fresh mulch to beds for extra insulation.
Winter: Check stored tubers occasionally for rotting. Discard any that are soft or spoiled. Order new tubers to plan next year’s dahlia garden!
FAQs About Designing and Planting a Dahlia Garden
What colors of dahlias go well together?
Some pleasing combinations include orange and purple, red and yellow, pink and white, and contrasting bicolors like red and yellow. Group varieties of the same color family for cohesion.
How much space do I need for dahlias?
Spacing depends on variety size. Dwarfs can be 8-12 inches apart, mid-size 2-3 feet apart, and giants up to 4 feet apart. Give them room to reach mature size without crowding.
Should dahlias be planted in groups or singly?
Planting in groups of 3, 5 or 7 creates a bolder display and shows off a variety’s color impact. But single specimen plants also stand out. Combine both approaches.
What are good companion annuals for dahlias?
Marigolds, zinnias, cosmos, snapdragons and cleome all combine well with dahlias. Choose annuals in similar heights and colors.
What perennials complement dahlias?
Late summer and fall perennials like asters, rudbeckia, sedum, chrysanthemums, goldenrod and grasses extend seasonal interest.
With endless options for incorporating dahlias, think creatively when designing your garden and containers. Play with colors, textures, heights and layouts until you have a winning plan. Then watch your dahlias steal the show with their vibrant, bountiful blooms.
Digging and storing tubers:
If you live somewhere where you need to store your tubers for the winter, here are some helpful tips:
- After the first frost, flowers & stems will immediately wilt. After another few strong frosts, leave them in the ground for a week or two.
- Pull out support cages and/or stakes.
- Dig outside the circumference of the tubers with a pitchfork. The bigger the plant, the bigger the tuber. But don’t worry—if you break or damage a tuber while digging, it won’t hurt the plant.
- To give yourself something to hold on to, cut off the dead stems about 2 to 3 inches above the bunch of tubers. Then, gently shake off as much dirt as you can.
- Place a tag on the cut stem for identification.
- In the bottom of a big cardboard box, put a few inches of peat moss or wood shavings.
- Give the tubers one last shake to get rid of any remaining dry dirt. Then, put them in the box in layers, with the bigger tubers at the bottom. When it’s about half full, add another layer of packing material and more potatoes. Cover the whole thing with the storage material, shake it to settle, and then add more storage material on top. Fold flaps to close.
- It’s best to keep things in a basement or garage that stays cool, but not freezing.
Dahlias can be bothered by aphids, stem borers, spider mites, and caterpillars. Additionally, powdery mildew, dahlia mosaic virus and fungal leaf spot can also cause problems.
This late-season border is mostly made up of magenta ‘Ambition’ and deep red ‘Nuit d’Eté.’ Blue Aster x frikartii ‘Mönch’ and gladioli fill in the blanks. These late bloomers pick up where summer-flowering plants leave off, giving the garden a grand sendoff for winter. Photo by: Marianne Majerus.
There are many ways to use dahlias in the garden. Here are a few tips and suggestions:
- Their lower stems aren’t always pretty, and the plants are heavy (especially the big-flowered dinnerplate types), so they tend to fall over if they aren’t staked. By putting them among other plants, you can support their weight and hide their lower stems.
- Taller dahlias look good with ornamental grasses and perennials in the back or middle of borders. Shorter dahlias look good with annuals or shorter perennials.
- Plant the smallest varieties in containers.
- Dahlia flowers are very bright, so look around at what other flowers or leaves are around you. The dahlias will pick up on these colors and make them stand out.
- Asters and yellow dahlias or purple dahlias are two examples of late-flowering perennials that go well together. Look for ones that have the same color but a different texture.
- They can also look surprisingly good with grasses because the contrast between the big, bright flowers and the finely textured grasses is so great.
- In more formal settings, the sharp leaves of clipped hedges can bring out their bright colors.
- Because their stems are longer, larger dahlias tend to be better for cutting.
Dahlias will be a beautiful sight in September, no matter how they are used. They will help the summer garden end on a high note.
CARE & STORAGE OF TUBERS
Cut out the center bud when the first set of leaves is about 8 to 12 inches high. This will help more stems grow and flowers appear. Sometimes this process is called topping.
Bone meal can be applied 2 to 3 times between June and October to encourage blooming. If your soil is healthy, this may not be needed at all. Apply an all-purpose fertilizer at planting to get them off to a good start.
As your dahlias grow, gently encourage the stems to stay inside the cage for support. Garden twine can be tied around the outside for additional support.
If you want longer, stronger stems and bigger flowers then you’ll need to remove the two pea-sized buds flanking the central bud. For certain types, it may be beneficial to remove more buds further down the plant. See this disbudding explanation from the Snhomish County Dahlia Society.
Deadheading will keep your plants looking tidy and encourage them to continue blooming. Many gardeners report that when they regularly deadhead their dahlias, they will bloom until the first frost. Be careful not to remove new buds, which are rounded—the spent flowers have a triangular or cone shape. Make your cut slightly higher than where the stem of the flower meets a main branch. After you cut off the spent flower, new buds will grow at this point, and in a few weeks you’ll have more flowers.
