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Delphinium 'Black Knight Group'

delphinium

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Stately spires of semi-double, deep purple flowers, opening in June and July on tall stems. These dark-eyed delphiniums look fantastic planted in bold clumps as part of a cottage-garden scheme or towards the back of a well-drained, sunny border, where they will add height and bold splashes of colour. They also make excellent cut flowers.

The double, deep blue petals transition to purple, terminating in a dark, unfathomable centre, making Delphinium 'Black Knight Group' a showcase summer plant with plenty of vertical and architectural interest and providing excellent cut flowers.

How to care for Delphinium Black Knight Group:

For best results, plant in an open spot with fertile, freely-draining soil and protect the young foliage against slug and snail damage.

During the growing season, apply a seaweed or balanced liquid fertiliser every 2-3 weeks. While wearing gloves, stake the emerging flower spike with a stout bamboo cane and tie it in as it grows.

Cutting back the faded flower stems to a flowering side shoot will help encourage a second flush of flowers.
Flowering period:
  • Jan
  • Feb
  • Mar
  • Apr
  • May
  • Jun
  • Jul
  • Aug
  • Sep
  • Oct
  • Nov
  • Dec
Eventual height:
1.7m
Eventual spread:
0.75m
Position:

Full sun

Rate of growth:

Average

Soil:

Moderately fertile, moist, well-drained soil

Hardiness:

Fully hardy

  • InformationThis perennial dies back to below ground level each year in autumn, then fresh new growth appears again in spring.
  • InformationHumans/Pets: Harmful if eaten

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RH30003502
9cm pot
£9.99
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(shipped within 2-3 working days)
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RH30004018
3 × 9cm pots
£22.99 £7.66 each
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(shipped within 2-3 working days)
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Delivery options (pick your preferred option at checkout)
Standard delivery Standard Delivery£5.95
Nominated delivery Named Day Delivery£10.95

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