Delphinium ‘Black Knight’ (Pacific Giant Series)

Description

Delphinium ‘Black Knight’ is a striking perennial with tall, dramatic spikes of deep violet-blue flowers. Reaching heights of up to 1.8m with a spread of 60cm, it blooms from June to July. Thriving in fertile, moist, well-drained soil and full sun, this Delphinium is hardy and attracts pollinators, making it a standout in perennial borders.

PLANTING and AFTERCARE GUIDE

Best Planting Time

• Spring: Plant Delphinium ‘Black Knight’ in spring when the soil begins to warm. This encourages strong root establishment before the flowering season.
• Autumn: Early autumn planting allows the crown to settle before dormancy and promotes vigorous growth the following year.

Site Selection

• Sunlight: Delphinium ‘Black Knight’ thrives in full sun to encourage tall, robust flower spikes but tolerates partial shade.
• Soil: Plant in fertile, moist, well-drained soil. Incorporate organic matter such as compost to improve fertility and drainage.

Planting Instructions

1. Prepare the Hole: Dig a hole twice the width of the root ball and equal in depth.
2. Soil Preparation: Mix in compost or well-rotted organic matter to enrich soil structure and nutrients.
3. Planting: Position the plant with the crown level to the soil surface. Backfill gently and firm the soil to remove air pockets.
4. Watering After Planting: Water thoroughly to settle the soil and support root establishment.

Watering Requirements

• Growing Season: Keep soil evenly moist during the growing season to support tall, sturdy flower spikes of Delphinium ‘Black Knight’. Avoid waterlogging, which can damage roots.
• Dormant Season: Reduce watering in winter, providing moisture only if the soil becomes very dry.

Feeding

• Spring: Apply a balanced fertiliser in early spring to give Delphinium ‘Black Knight’ a strong start, supporting robust growth and vibrant blooms.
• Mid-Summer: Feed again during flowering to maintain plant vigour and prolong bloom.

Pruning

• Deadheading: Remove spent flowers to encourage further blooming and keep Delphinium ‘Black Knight’ tidy.
• Autumn Pruning: Cut back to ground level after flowering to prepare the plant for dormancy and ensure healthy regrowth.

Mulching

• Spring: Apply mulch around the base to conserve moisture, suppress weeds, and regulate soil temperature.
• Winter: After pruning, add a thicker mulch layer to protect the crown and encourage strong regrowth next season.

Supporting the Plant

• Staking: Delphinium ‘Black Knight’ has tall stems that benefit from staking to prevent bending or breakage. Install supports early to avoid disturbing the roots.

Final Tips

Delphinium ‘Black Knight’ is a hardy, pollinator-friendly perennial that delivers stunning violet-blue spikes, adding height and drama to any border. With fertile soil, consistent watering, and staking, Delphinium ‘Black Knight’ will provide impressive blooms from June to July. Ideal for full sun or partially shaded locations, it is a must-have for striking perennial displays.

RHS Details

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