Black Foliage Dahlia: How to Grow Dahlia Black Forest Ruby
Dahlia ‘Black Forest Ruby’ may have a dark and mysterious name, but rest assured, it’s here to slay in the garden, not in a crime novel! With its deep black foliage and vibrant ruby-red blooms, this dark leaf dahlia is a true showstopper in any garden.
This striking variety produces an abundance of double to semi-double flowers, creating a rich contrast against deep black leaves.
Supported by sturdy, upright stems that won’t flop, Dahlia Black Forest Ruby maintains a tidy and polished appearance throughout the season. Among black leaf dahlia varieties, its impressive disease resistance and non-stop blooms make it one of the most reliable choices for the garden.
Dahlias with dark foliage add a dramatic touch to flower beds, borders, and containers, making them a favorite for bold, eye-catching designs.
Dahlia Black Forest Ruby is a 2025 All-America Selections winner, earning this recognition from the non-profit plant trialing organization for its outstanding garden performance. To learn more about their work, visit the AAS website.
Let’s take a closer look at how to grow this captivating black foliage dahlia and explore creative ways to incorporate its dark beauty into your landscape.
Dahlia Black Forest Ruby. Image courtesy of All-America Selections, All-AmericaSelections.org
Are Black Foliage Dahlias Perennial?
Dahlias are technically tender perennials, meaning they can survive year after year in the right conditions, but their tubers cannot tolerate freezing soil. Black foliage dahlias like Black Forest Ruby are hardy in USDA zones 9-11, where mild winters allow tubers to stay in the ground and return each season. Not sure of your zone? Check the USDA Plant Hardiness Zone Map to find out.
In colder zones (8 and below), dahlias are treated as annuals unless you overwinter the tubers. The process is simple: dig them up before a hard freeze, store them in a cool dry place, and replant in spring. With that one extra step, you can enjoy these dramatic black leaf dahlias year after year regardless of your climate.
A sea of ruby-red blooms against deep black foliage. Dahlia Black Forest Ruby is one of the most dramatic dahlias for containers and garden beds alike. Image courtesy of All-America Selections, All-AmericaSelections.org
How to Plant Black Foliage Dahlias
Planting dahlias correctly is key to getting the best blooms, whether you’re starting from tubers or purchasing container-grown plants from a nursery.
These sun-loving flowers thrive in full sun, meaning they need at least 6-8 hours of direct sunlight per day to flourish. They also prefer well-draining soil with a slightly acidic to neutral pH (around 6.5-7.0). Dahlias do not like clay soil.
If you’re planting dahlia tubers, wait until all danger of frost has passed and the soil has warmed up in spring. Choose a spot with good drainage, and plant the tubers 4-6 inches deep, with the "eye" (the small growing point) facing upward.
Avoid watering immediately after planting, since excess moisture can cause rot. Wait until sprouts emerge before beginning a regular watering schedule. If you are new to gardening, read more about watering in “How to Water Your Plants”.
For container-grown dahlias purchased from a nursery, planting is even easier! Simply dig a hole as deep and as wide as the container, then gently remove the plant and set it in the hole at the same depth as it was in the pot.
Firm the soil around the roots and water thoroughly to help the plant settle in. Since these plants are already growing, they will need consistent watering. Keep the soil evenly moist but not soggy.
Whether you start with tubers or potted plants, providing the right conditions from the start will set your dahlias up for a season of stunning blooms!
When to Plant Black Foliage Dahlias
Timing is crucial when planting dahlias to ensure healthy growth and abundant blooms. Dahlias are warm-season plants that thrive in mild to warm temperatures, so they should be planted after the risk of frost has passed.
In most regions, this means waiting until mid to late spring, when the soil has warmed up to at least 60°F (16°C). Planting too early in cold, wet soil can cause the tubers to rot or delay sprouting.
If you live in a colder climate (zones 8 and below) and want to get a head start, you can pre-sprout tubers indoors about 4-6 weeks before your last expected frost.
Simply place them in pots with well-draining soil, keep them in a warm, bright location, and transplant them outside once conditions are right.
For gardeners in warmer climates (zones 9-11), dahlias can be planted directly in the ground in early spring and, in some cases, left in the ground year-round.
No matter your location, be sure to choose a planting time that allows for at least 90-120 days of warm weather so your dahlias have plenty of time to grow and bloom before cooler temperatures return.
Up close, the drama of this black foliage dahlia is undeniable. Velvety red blooms set against jet-black leaves that get darker the more sun they receive. Image courtesy of All-America Selections, All-AmericaSelections.org
Are Black Foliage Dahlias Deer-Resistant?
Dahlias are not deer resistant. Deer won't seek them out as a preferred food source, but they will eat dahlias when pickings are slim. It’s worth keeping in mind if deer are frequent visitors to your garden.
Rutgers University rates them as “occasionally severely damaged” on their list of Landscape Plants Rated by Deer Resistance.
If you live in an area with high deer pressure, it's important to keep this in mind when choosing dahlias for your garden.
For those seeking a striking black foliage plant without the high risk of deer damage, consider Astilbe 'Dark Side of the Moon', as deer tend to avoid astilbes altogether.
Where to Plant Dahlia Black Forest Ruby
Container garden: Dahlia Black Forest Ruby is one of the most dramatic dahlias for containers, stunning in patio and balcony pots, or flanking an entryway.
Eclectic Garden: Pair this black foliage dahlia with a mix of vibrant and unexpected colors, like the electric blue flowers of Salvia ‘Black and Bloom’ or the bright yellow flowers of Black-Eyed Susans.
Goth Garden: Black foliage dahlias are ideal for a gothic garden and pair beautifully with other dark-leaved gothic garden plants.
Cottage Garden: Incorporate Dahlia Black Forest Ruby alongside classic cottage garden favorites like lavender, roses, and hollyhocks for a striking contrast.
Borders and Flower Beds: Use this dahlia as a focal point or anchor in mixed borders and flower beds, planting it next to soft-textured foliage plants like lamb’s ear or ferns, or alongside other dark foliage annuals.
Cutting Garden: Plant black foliage dahlias in a sunny cutting garden alongside zinnias and sunflowers for striking arrangements you can bring indoors.
Planting Companions for Black Forest Ruby Dahlia
Cardinal flower (Lobelia cardinalis)
Japanese painted fern (Athyrium niponicum)
Other dahlias, like ‘Mystic Spirit’, ‘Black Jack’, or ‘Black Narcissus’
Red, yellow, or salmon-colored zinnias like ‘Senora’, ‘Old Mexico’, or ‘Garnet Treasure’
Autumn Joy stonecrop (Sedum/Hylotelephium ‘Herbstfreude’)
Sahin’s Early Flowerer sneezeweed (Helenium ‘Sahin’s Early Flowerer’)
Helene von Stein lamb’s ears (Stachys byzantina ‘Helene von Stein’)
Brilliance Autumn Fern (Dryopteris erythrosora 'Brilliance')
Glazed and Infused coral bells (Heuchera ‘Glazed and Infused’ Dolce®)
Cheyenne Spirit coneflower (Echinacea ‘Cheyenne Spirit’)
Winecraft Black® Smokebush (Cotinuscoggygria 'NCCO1' Winecraft Black®)
Dahlia Black Forest Ruby Plant Profile
Common name: Dahlia Black Forest Ruby
Botanical/Latin name: Dahlia pinnata ‘Black Forest Ruby’
Hardiness zones: 9-11
Native range: Mexico and Central America
Mature size: 20-27 inches high and 10-14 inches wide
Spacing: 6-10 inches on center
Light requirements: Full sun
Form: Upright
Growth rate: Fast
Flowering time: Summer to frost
Flower color: Red
Flower form: Double to semi-double
Wildlife value: Attracts butterflies, bees and pollinators
Deer resistant: No
Other Black Leaf Dahlia Varieties Worth Growing
If the drama of black foliage dahlias has you hooked, Black Forest Ruby is just the beginning. Here are a few other dark-leafed varieties worth adding to your list:
Bishop of Llandaff: A classic and widely available dark-leafed dahlia with deep burgundy-black foliage and vivid scarlet semi-double blooms. Grows 3-4 feet tall and has been a garden favorite for decades.
Mystic Illusion: A compact black leaf dahlia with striking yellow flowers that pop beautifully against near-black foliage. A great choice for containers and smaller garden spaces.
Happy Single Romeo: Deep red single blooms on dark stems with near-black foliage. Compact, pollinator-friendly, and a strong performer in beds and borders.
More Dark Foliage Plant Inspiration
Love the drama of dark foliage? Here's how to design a full gothic garden with plants that complement your black foliage dahlias:
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