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Delphinium Black Knight Group
Delphinium Black Knight Group

Delphinium Black Knight Group

SKU: RH30004018
3 × 9cm pots
£22.99 £11.50 £3.83 each
In stock (despatch in 2-3 working days)
9cm pot
£9.99 £4.99
In stock (despatch in 2-3 working days)
1

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Overview

Spikes of dark purple flowers with black centres. 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.

Specifications

  • Position: full sun
  • Soil: fertile, well-drained soil
  • Rate of growth: average
  • Flowering period: June and July
  • Hardiness: fully hardy
  • Toxicity: Harmful to humans and pets if eaten

Eventual height & spread

Eventual height and spread

Care guide

Protect young foliage against slug and snail damage in spring. Stake with bamboo canes in mid-spring, before the flowers appear. During the growing season, apply a balanced liquid fertiliser every 2-3 weeks and wearing gloves cut back the faded flower-stems to a flowering side-shoot to encourage repeat flowering. At the end of autumn cut back and compost the faded flower stems.

Warning

Humans/Pets: Harmful if eaten

How your order will arrive

Pots and Packaging
Our 9cm pots are given extra packaging to protect the plant. This extra packaging consists of a recyclable plastic blister pack which is then placed in a cardboard box for delivery.

Preparation
The nursery will ensure the plant is moist while it's waiting to be picked up. Our quality control team waters the plant before packing them where necessary to make sure that the plant is suitably watered for transport. Plants with long delicate stems are secured with canes to prevent damage.

Plant on Arrival
Typically plants are delivered ready to plant and will take some time to settle, grow and look more like the product image above.

About Primrose

About Primrose

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If you'd like to find out more, check out our 'About Us' page.

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© 2025 Cercis Ltd. All rights reserved | Primrose is the trading name of Cercis Ltd (Registration number: 14521244)

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© 2025 Cercis Ltd. All rights reserved | Primrose is the trading name of Cercis Ltd (Registration number: 14521244)