Dahlias are half hardy, so keep them protected from frost. Pot tubers individually between February and April and grow them on in a greenhouse or bright indoor position. Alternatively, start them outside in May, once the risk of frost has passed.
Out of season
Amaze yourself and all your neighbours with the enormous, spectacular flowers of Dahlia 'Penhill Dark Monarch' – you simply won’t be able to believe your eyes when these impressive blooms open! This trendy dinnerplate dahlia is without doubt extremely dishy, with layers upon layers of fantastic two-tone pink and apricot blooms. Not only will they shine like beacons in the garden, but you certainly won’t be without top-notch cutting material. Just one of these big blooms will pack a real punch whether it’s on its own in a vase or forming part of a mixed bouquet.
Dahlia 'Penhill Dark Monarch's Unbelievably big blooms growing on tall, bushy plants, these larger-than-life dahlias are a real centrepiece. Perfectly positioned in a sunny border, you can enjoy a long-lasting reward of blooms which are produced continuously throughout the summer months and well into autumn. Cut the flowers when they’re at their peak and more will grow in their place!
Quantity
Plant profile
Plant calendar
For planting out later, use a snug-fitting 15–20cm pot filled with peat-free multipurpose compost. For a patio display, plant directly into a container at least 30cm wide and keep it somewhere bright and frost free until it can move outdoors.
Position the old stem facing upwards, with the tubers covered and the stem stump level with the compost. Tubers naturally vary in size and shape and may arrive without visible buds. Bent necks are usually fine if they remain firmly attached, so do not remove them.
Water after planting, then allow the compost to become almost dry before watering again while the tuber remains dormant. Once shoots and leaves are growing strongly, water more regularly, always allowing excess water to drain away.
Plant out after the last frost, once the plant is around 20–30cm tall and its roots hold the compost together. Space dahlias approximately 30–50cm apart in borders, allowing less room for compact varieties. Water thoroughly after planting.
Water regularly during active growth and deadhead or cut flowers often. Dahlias usually bloom from July or August until the first frost, although later-planted tubers may start in late August or September. In autumn, lift, clean and dry the tubers, then store them somewhere cool, dry, airy and frost free.
- Botanical name
- Dahlia 'Penhill Dark Monarch'
- Flower colour
- Pink, coral
- Tuber size
- 1
- Established height
- 1.2-1.5m
- Established spread
- 50-70cm
- Growing skill
- Easy to grow
- Habit
- Upright
- Hardiness
- Half hardy
- Leaf colour
- Green
- Mouse resistant
- No
- Plant spacing
- 5 tubers per m2
- Pollinator friendly
- No
- Position
- Sheltered
- Rabbit resistant
- No
- Scented
- No
- Soil acidity
- Any
- Soil moisture
- Free draining
- Soil type
-
Loam
Sandy
Multipurpose compost
Loam-based compost - Suitable for
-
Large containers
Borders
Gravel gardens
Coastal gardens
Cottage gardens
Low maintenance gardens
Cut flower gardens - Sunlight
-
Full sun
Partial shade - Toxicity
- No report
- Years to establish
- 1st year
Good for cutting
Thrives in full sun
Perennial
Packed in paper
Low maintenance
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Dahlia 'Penhill Dark Monarch' reviews
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