Dahlia 'Bishop of Llandaff'
Dahlia 'Bishop of Llandaff' · Asteraceae
Semi-double flowers of pure, glowing scarlet over finely cut, near-black foliage. Raised in Cardiff in 1924 and never surpassed.
- Size
- 3½ ft tall, 24 in wide
- Zones
- 8 to 10
- Light
- Full sun
- Flowers
- Mid July to mid October
- Pets
- Toxic (mild)
- Job in a bed
- Drift
A bed built around dahlia 'Bishop of Llandaff'
The planner designed this bed around dahlia 'Bishop of Llandaff' when this page was made: a 12 × 6 ft (3.7 × 1.8 m) English border in zone 8, full sun. It chose the other plants from the 872 that suit those conditions, and says below why dahlia 'Bishop of Llandaff' stands where it does.
The plants
- 1 Yellow ice plant × 8, yellow
- 2 October daphne × 3, pink
- 3 Little bluestem 'Standing Ovation' × 4, tan
- 4 Italian bugloss 'Dropmore' × 3, blue
- 5 Inkberry 'Gem Box' × 1, dark green leaves
- 6 Purple coneflower × 3, purple
- 7 Dahlia 'Bishop of Llandaff' × 1, red
- 8 Star of Persia × 3, purple
Why this plant
- The only red.
Why here
- In the middle. At 3½ ft it is seen over yellow ice plant (2 in) in front of it.
- One plant. Three or more is usual for a plant of this kind, and reads better.
Why now
- In flower for 15 weeks. From mid July to mid October.
- Part of the bed's peak. With Italian bugloss 'Dropmore' and purple coneflower in mid July: 3 kinds at once. No week has more.
Planned as an English border: 6 of the 6 groups (100%) are drifts, longer along the bed than they are deep. The scheme leans cool (pink, blue and purple) and uses yellow and red for warmth, with tan to calm things between them. When the flowers are over, three kinds, among them yellow ice plant and little bluestem 'Standing Ovation', keep the bed from looking bare.
The planner's own design check: 11 Excellent, 5 Good, 1 Satisfactory. It flags one thing to watch: Nothing on this plan is highly poisonous or an aggressive spreader.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where dahlia 'Bishop of Llandaff' goes in a border
At 3½ ft it belongs in the middle of a bed. In the planner's ten height classes it is moderately tall (3 to 4 ft).
Its job: drift. Planted in a small group of three or five, and repeated further along in the other number.
The dahlia that made dahlias respectable in mixed borders. Its dark leaves work as foliage long before it flowers. Lift the tubers after the first frost in cold areas.
- Dark foliage and scarlet flowers
- Hot borders in late summer
- Bees, which can reach its open centre
What to plant with dahlia 'Bishop of Llandaff'
Plants recorded as good partners for it, and what each pairing does:
- Canna: in flower together for 13 weeks, from mid July; bold leaves against its fine ones; happy in the same moist soil.
- Sneezeweed: in flower together for eight weeks, from early August; grows up in time to hide its dying leaves; happy in the same moist soil.
- Dwarf fountain grass 'Hameln': in flower together for nine weeks, from late July; grows up in time to hide its dying leaves.
Questions about dahlia 'Bishop of Llandaff'
Does dahlia 'Bishop of Llandaff' need sun or shade?
Dahlia 'Bishop of Llandaff' grows in full sun (6 or more hours of direct sun a day).
It wants soil that stays evenly moist, rich in organic matter, and plenty of water.
What zones does dahlia 'Bishop of Llandaff' grow in?
USDA zones 8 to 10. It is hardy to zone 8, which means it survives winter nights down to about 20 °F (−7 °C).
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
When does dahlia 'Bishop of Llandaff' flower in my zone?
In zone 5 it flowers mid July to mid October. As a summer flower it moves about half a week for every zone: earlier where it is warmer.
| Zone 8 | Early July to mid October |
|---|---|
| Zone 9 | Late June to mid October |
Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.
How far apart should dahlia 'Bishop of Llandaff' be planted?
20 in (50 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 24 in (60 cm), so a group knits into one patch.
It grows 3½ ft (100 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many dahlia 'Bishop of Llandaff' plants do I need?
At 20 in apart, set out in staggered rows:
- 4 to fill 10 square feet (about 1 m²)
- 7 for a single row 10 ft (3 m) long
- 14 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as a group of three or five, with a second group further along in the other number.
In the bed above, the planner used one in one group.
Is dahlia 'Bishop of Llandaff' poisonous to dogs and cats?
Yes: mild toxicity to people, dogs, cats and horses. Can cause mild stomach upset in pets if eaten. Handling the plant can irritate skin.
Rated from the ASPCA. Where references disagree, the more cautious rating is used.
Is there a pet-safe plant like dahlia 'Bishop of Llandaff'?
These come closest to doing what dahlia 'Bishop of Llandaff' does, and no toxicity is recorded for them:
- Crocosmia 'Lucifer': the same job in a bed and the same colour; 12 in narrower, flowers mid July to mid August.
- Bee balm 'Raspberry Wine': the same job in a bed and the same colour; 4 in wider, flowers late June to mid August.
- False sunflower 'Summer Sun': the same job in a bed and the same size; flowers late June to early September, yellow, not red.
Matched the way the planner's Swap button matches plants: the same job in a bed, then size, then flowering time.
What can I plant to hide dahlia 'Bishop of Llandaff''s leaves after it flowers?
A bulb's leaves have to be left to yellow for about six weeks after flowering, to feed next year's flowers. Plant it among perennials that come up late and spread wide, and they grow over the leaves as they fade:
- Blue false indigo: 4 ft tall and 4 ft wide, in flower late May to mid June.
- Itoh peony 'Bartzella': 3 ft tall and 3½ ft wide, in flower late May to mid June.
- Armenian cranesbill: 3½ ft tall and 3½ ft wide, in flower mid June to late July.
What does dahlia 'Bishop of Llandaff' look like in winter?
Dahlia 'Bishop of Llandaff' is underground: it dies back after flowering and waits as a bulb until spring. Mark where it is, so a fork does not find it first.
More Dahlia
- Dahlia Dahlia pinnata
- Dahlia 'Café au Lait' Dahlia 'Café au Lait'
In these guides
Every fact on record
- Type
- Bulb
- Size
- 3½ ft (100 cm) tall, 24 in (60 cm) wide
- Plant
- 20 in (50 cm) apart
- Height class
- Moderately tall (3 to 4 ft)
- Place in the bed
- Middle
- Flowers
- Mid July to mid October; daisies; red
- Leaves
- Fine texture, herbaceous; black, purple
- Shape
- Upright, clumping
- Hardy in
- USDA zones 8 to 10
- Light
- Full sun
- Soil
- Rich, evenly moist
- Water
- High
- Feeding
- Moderate, in spring
- Family
- Asteraceae
Checked against ASPCA poison lists. Flowering times are for zone 5: later in colder zones, earlier in warmer ones. Toxicity and spread information is a general gardening guide, not veterinary or medical advice, and invasive status varies by region. If a person or pet eats a plant, contact poison control or a vet. Check your local invasive species list before planting anything with a spread warning.