Source: Bishop of Llandaff dahlia (Dahlia ‘Bishop of Llandaff’) short overview
Dahlia 'Bishop of Llandaff' is a historic, tuberous dahlia valued for the striking contrast between vivid red semi-double blooms and deeply divided dark bronze-purple foliage. It performs best in full sun with fertile, well-drained soil and even moisture. Flowering continues from midsummer into fall, making this cultivar useful in borders, containers, pollinator plantings, and cut-flower gardens. Lift and store the tubers where winter frost is severe.
Taxonomic classification
Bishop of Llandaff dahlia (Dahlia ‘Bishop of Llandaff’) care guide
Light and placement
Provide full sun, ideally with at least 6–8 hours of direct light and a sheltered south- or west-facing position. Strong light supports flowering and helps maintain the dark foliage color. Thin, weak stems and sparse flowering suggest insufficient light; scorched foliage or rapid wilting suggests excessive heat combined with inadequate water rather than too much light alone.
Watering and humidity
Water deeply when the upper soil begins to dry, keeping moisture even during active growth without leaving the soil saturated. Container plants may need more frequent watering in hot weather. Water at the base in the morning to reduce foliar disease. Reduce watering after frost and dormancy, and keep stored tubers dry enough to prevent rot.
Soil and growing medium
Use fertile, humus-enriched soil that drains freely but does not dry rapidly. Loam or amended sandy soil is suitable; heavy clay should be loosened with organic matter and drainage improvements. Published guidance allows a broad pH range, from acidic through alkaline, so a neutral to slightly acidic or slightly alkaline garden soil is acceptable if nutrient availability is good.
Feeding
Incorporate mature compost before planting, then feed only after active growth begins. Use a balanced or lower-nitrogen fertilizer at label strength, repeating according to the product directions during the growing season. Avoid heavy nitrogen feeding, which can produce lush foliage and weaker flowering; stop feeding as plants approach dormancy.
Growth and habit
A vigorous, upright, branching plant develops from tubers during warm weather. Regular deadheading encourages continued flowering, while staking helps maintain orderly stems in exposed locations. Dark foliage remains a major ornamental feature before and between flowering flushes.
Planting and repotting
Plant tubers outdoors after the danger of frost has passed and the soil has warmed. Set the tuber horizontally about 5 inches deep, with the eyes facing upward. Water lightly until shoots appear, then increase watering as growth develops. Allow room for an upright, branching plant and stake early if exposed to wind.
For containers, transplant or shift plants before roots become crowded. Use a large container with drainage holes and a fertile, moisture-retentive but free-draining potting mix. Container-grown plants may need support as stems lengthen.
Propagation and pruning
Propagation
Divide stored tubers in spring, ensuring each division has at least one healthy eye. Softwood cuttings can also be taken from actively growing shoots. Seed does not reliably reproduce the named cultivar, so division is preferred for maintaining its characteristics.
Pruning
Pinch or trim the growing tip when plants are young if bushier branching is wanted. Remove spent flower heads regularly and cut stems for arrangements. After frost blackens the foliage, cut the plant back before lifting or storing the tubers.
Overwintering
After the first killing frost, cut back blackened stems, lift tubers in regions with hard or wet winters, and allow them to dry briefly before storing in a cool, dark, frost-free place in barely moist packing material. Check periodically for rot or shriveling. In mild climates, heavy mulch may help, but winter survival is not guaranteed.
Uses
Valued as a colorful border plant, container specimen, pollinator-friendly ornamental, and long-stemmed cut flower. The dramatic foliage also provides contrast in mixed plantings. It has no established culinary use, and all plant parts should be kept away from pets and children because ingestion may cause adverse effects.
Appearance
The cultivar is identified by deeply divided foliage in dark bronze, purple, and near-black-green tones, contrasting with vivid red flower heads. Stems are upright and branching, while the blooms have a relatively open center compared with highly double dahlias. The foliage color is strongest in bright light and is a key identification feature.
Flowering
This cultivar produces bright red, peony-form semi-double flower heads with yellow anthers. Blooms develop over a long summer-to-fall season and usually continue until the first hard frost if spent flowers are removed and plants remain actively growing.
Pollination and visitors
The open center of the single to semi-double flower form gives visiting insects access to pollen and nectar. Reliable horticultural sources describe the cultivar as attractive to wildlife or visiting pollinators, but a specific pollinator species has not been consistently documented for this exact cultivar.
Dahlia 'Bishop of Llandaff' photos
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Diseases and pests
Diseases
Reduce disease pressure with full sun, good air circulation, clean planting stock, and watering at the soil surface rather than over the foliage. Watch for powdery mildew, wilts, viruses, crown gall, and root rot. Remove badly affected plants and avoid replanting contaminated tubers or soil.
Pests
Inspect foliage for aphids, caterpillars, leafhoppers, slugs, and snails. Hand-pick larger pests, protect young growth where necessary, and encourage beneficial insects. Avoid routine broad-spectrum insecticides during bloom. Virus symptoms warrant removal of affected plants and sanitation of tools.
Toxicity and pollen
Dahlias are listed as toxic to dogs and cats by the ASPCA, with mild gastrointestinal upset and mild dermatitis reported. The RHS also warns that all parts may cause severe discomfort if ingested and may irritate skin. Prevent pets and children from eating the plant, and wear gloves if handling causes irritation.
- Typical season
- Late spring through fall during flowering
- Pollination / pollen
- Primarily insect-associated pollen; limited airborne dispersal
Dahlia pollen is generally released from the flower anthers rather than dispersed freely by wind, so airborne exposure is usually lower than for wind-pollinated plants. The open blooms can still expose visitors and people nearby to pollen, and sensitive individuals should judge their own response rather than assume zero allergy risk.
Native habitat
This is a cultivated garden hybrid rather than a wild habitat specialist. Dahlias originate from upland and montane regions of Mexico and Central America, while this cultivar is grown in fertile, sunny garden soils with a distinct warm-season growth period and frost-free storage requirement.
Interesting fact
The cultivar is a historic named dahlia associated with Cardiff nurseryman Fred Treseder and was named for Joshua Pritchard Hughes, Bishop of Llandaff. Its unusually dark foliage provides strong contrast with the red flowers. It is also a parent of the seed-grown 'Bishop's Children' strain, which does not come true to the named cultivar.
Frequently asked questions (FAQ)
The most relevant questions about this plant, with short and direct answers.
🌱Quick care
What is Dahlia 'Bishop of Llandaff'?⌄
Dahlia 'Bishop of Llandaff' is a tuberous, peony-flowered dahlia grown for bright red blooms and deeply divided, dark bronze-purple foliage. It typically reaches about 3 to 4 feet tall in a sunny garden.
How much sun does Dahlia 'Bishop of Llandaff' need?⌄
Dahlia 'Bishop of Llandaff' needs full sun, ideally at least 6 hours of direct light daily. A sheltered location helps protect its stems from strong winds.
How often should I water Dahlia 'Bishop of Llandaff'?⌄
Water Dahlia 'Bishop of Llandaff' whenever the soil surface begins to dry, keeping the soil evenly moist but not soggy. Water deeply at the base during hot or dry weather rather than giving frequent shallow sprinklings.
How tall does Dahlia 'Bishop of Llandaff' get?⌄
Dahlia 'Bishop of Llandaff' commonly grows about 3 to 4 feet tall and roughly 1 to 1½ feet wide. Height can vary with soil fertility, moisture, climate, and whether the plant is grown in a container.
🌤️Environment and placement
What soil is best for Dahlia 'Bishop of Llandaff'?⌄
Use fertile, humus-rich, well-drained soil for Dahlia 'Bishop of Llandaff'. Improve poor soil with compost, but avoid locations that stay waterlogged because tubers can rot.
Can Dahlia 'Bishop of Llandaff' grow in a container?⌄
Yes, Dahlia 'Bishop of Llandaff' grows well in a large container with drainage holes and fertile, well-drained potting mix. Choose a container heavy enough to remain stable and water consistently because containers dry out faster than garden soil.
Where should I plant Dahlia 'Bishop of Llandaff' in the garden?⌄
Plant Dahlia 'Bishop of Llandaff' in a sunny, sheltered border, raised bed, or patio container with good air circulation. Its dark foliage and red flowers work especially well near the front or middle of a mixed planting.
Is Dahlia 'Bishop of Llandaff' hardy in the United States?⌄
Dahlia 'Bishop of Llandaff' is frost tender and is not reliably winter-hardy across much of the United States. In colder USDA zones, lift and store the tubers after frost; in mild areas, a thick, dry mulch may provide adequate protection, but survival is not guaranteed.
💧Care and problems
Does Dahlia 'Bishop of Llandaff' need staking?⌄
Dahlia 'Bishop of Llandaff' may need staking, especially in windy sites, fertile soil, or areas with heavy rain. Install a stake or support early so it can be tied in as the stems grow.
Should I pinch Dahlia 'Bishop of Llandaff'?⌄
Pinch the growing tip of Dahlia 'Bishop of Llandaff' when the plant is about 12 to 18 inches tall to encourage branching and a bushier shape. Avoid pinching after flower buds have begun forming if earlier blooms are important.
How do I deadhead Dahlia 'Bishop of Llandaff'?⌄
Deadhead Dahlia 'Bishop of Llandaff' by cutting spent flower stems back to a strong set of leaves or a side shoot. Regular removal of faded flowers encourages continued blooming until frost.
What fertilizer does Dahlia 'Bishop of Llandaff' need?⌄
Feed Dahlia 'Bishop of Llandaff' with compost or a balanced fertilizer during early growth, then use a lower-nitrogen, higher-potassium fertilizer once flowering begins. Excess nitrogen can produce lush foliage with fewer flowers.
Why is my Dahlia 'Bishop of Llandaff' not flowering?⌄
Dahlia 'Bishop of Llandaff' may fail to flower because of insufficient sun, late planting, drought, excessive nitrogen, overcrowding, or tuber damage. Give it full sun, even moisture, good drainage, and time to establish before expecting heavy bloom.
What pests commonly affect Dahlia 'Bishop of Llandaff'?⌄
Aphids, earwigs, caterpillars, and slugs or snails may damage Dahlia 'Bishop of Llandaff'. Inspect new growth and flower buds regularly, and use the least-toxic control appropriate for the pest and your garden.
Why are the tubers of Dahlia 'Bishop of Llandaff' rotting?⌄
Dahlia 'Bishop of Llandaff' tubers usually rot when they remain too wet, are stored before drying, or are exposed to freezing temperatures. Store only firm, healthy tubers in a cool, frost-free place with slightly moist, breathable packing material.
🪴Planting and repotting
When should I plant Dahlia 'Bishop of Llandaff' tubers in the United States?⌄
Plant Dahlia 'Bishop of Llandaff' tubers outdoors after the danger of frost has passed and the soil has warmed. In colder areas, start tubers indoors several weeks earlier and transplant them after hardening off.
How deep should I plant Dahlia 'Bishop of Llandaff' tubers?⌄
Plant Dahlia 'Bishop of Llandaff' tubers about 4 to 6 inches deep with the eyes facing upward or the stem end slightly above the tuber. Avoid planting into cold, saturated soil, which can delay growth or cause rot.
How far apart should I plant Dahlia 'Bishop of Llandaff'?⌄
Space Dahlia 'Bishop of Llandaff' plants about 18 to 24 inches apart to allow room for branching and air circulation. Wider spacing may be useful in humid climates or very fertile soil.
Can I start Dahlia 'Bishop of Llandaff' indoors?⌄
Yes, start Dahlia 'Bishop of Llandaff' tubers indoors in pots several weeks before outdoor planting time. Keep the mix lightly moist and place the pots in bright light, then harden the plants off before transplanting after frost danger passes.
✂️Propagation and pruning
How do I divide Dahlia 'Bishop of Llandaff' tubers?⌄
Divide Dahlia 'Bishop of Llandaff' tubers in spring so each section includes a firm piece of crown and at least one viable eye. Discard soft or diseased portions, and allow fresh cuts to dry briefly before planting.
Can Dahlia 'Bishop of Llandaff' be grown from cuttings?⌄
Yes, Dahlia 'Bishop of Llandaff' can be propagated from softwood cuttings taken from actively growing shoots on a stored tuber. Root the cuttings in a clean, free-draining medium under bright light and maintain steady moisture.
Can I grow Dahlia 'Bishop of Llandaff' from seed?⌄
You can grow dahlias from seed, but seedlings will not reliably reproduce the exact characteristics of Dahlia 'Bishop of Llandaff'. Division or cuttings are preferred when you want true-to-type plants.
When should I cut back Dahlia 'Bishop of Llandaff'?⌄
Cut Dahlia 'Bishop of Llandaff' back after the first frost blackens the foliage, leaving a short stem to help locate the crown. Wait until frost has affected the top growth because the tuber can continue storing energy while the foliage remains healthy.
⚠️Toxicity and safety
Is Dahlia 'Bishop of Llandaff' toxic to dogs and cats?⌄
Dahlia 'Bishop of Llandaff' should be treated as toxic to dogs and cats if eaten, with possible mild gastrointestinal upset or skin irritation. Keep tubers and plant material away from pets and contact a veterinarian if ingestion occurs.
Is Dahlia 'Bishop of Llandaff' poisonous to people?⌄
Dahlia 'Bishop of Llandaff' may cause discomfort if ingested and can irritate skin in sensitive people. Wear gloves when handling the plant or tubers, and keep plant material away from children.
🌸Flowering and special interest
When does Dahlia 'Bishop of Llandaff' bloom?⌄
Dahlia 'Bishop of Llandaff' generally blooms from mid- to late summer into fall, often continuing until the first hard frost. Consistent moisture, full sun, and regular deadheading support a longer display.
What do the flowers of Dahlia 'Bishop of Llandaff' look like?⌄
Dahlia 'Bishop of Llandaff' produces bright red to vermilion-red, semi-double peony-shaped flowers with yellow centers. The blooms contrast strongly with its dark bronze-purple, finely divided foliage.
Is Dahlia 'Bishop of Llandaff' good for cut flowers?⌄
Yes, Dahlia 'Bishop of Llandaff' is suitable for cutting and can produce flowers over a long season. Cut stems when the flowers are fully open, because unopened dahlia buds may not open well after cutting.
Does Dahlia 'Bishop of Llandaff' attract pollinators?⌄
Dahlia 'Bishop of Llandaff' can provide accessible pollen and nectar for bees because its semi-double flowers retain an exposed central area. It is generally more pollinator-friendly than densely double dahlia cultivars.
How do I overwinter Dahlia 'Bishop of Llandaff' tubers?⌄
After frost blackens the foliage, cut the plant back, lift the tubers carefully, and let them dry before storing. Keep them in a cool, dark, frost-free location packed in barely moist vermiculite, peat-free mix, or similar material, and check periodically for rot or shriveling.
