RHS Delphinium Centurion Sky Blue F1 Seeds 20 Seeds, Hardy Perennial Blue Flower Spikes

RHS Delphinium Centurion Sky Blue F1 Seeds by Mr Fothergill’s produce tall, dramatic flower spikes in a striking sky blue shade with soft white centres. This hardy perennial delivers impressive first year flowering and is ideal for adding height and structure to the back of sunny borders.

Plants grow to approximately 150cm in height with a spread of around 45cm. The densely packed flower spikes create strong vertical impact from June to September, making this variety a standout feature in cottage gardens and traditional planting schemes.

Delphinium Centurion Sky Blue F1 is recognised for its high quality performance and holds the RHS Award of Garden Merit, confirming its reliability in UK growing conditions. The seed range is produced by Mr Fothergill’s in partnership with the Royal Horticultural Society.

This variety prefers full sun and fertile, well drained soil. Tall stems may benefit from support in exposed areas. Removing spent flower spikes can encourage further blooms.

For indoor sowing, sow from February to April in trays of moist compost. Cover lightly and keep at 15 to 18C. Seedlings appear in 21 to 42 days. When large enough to handle, transplant individually into 7.5cm pots. Gradually acclimatise outdoors in late May, avoiding frost, then plant 35cm apart in flowering position.

For outdoor sowing, sow from May to July in a prepared seed bed. Sow thinly in rows 20cm apart. Cover lightly with fine soil and keep moist. Transplant 35cm apart in autumn.

Plants flower from July to September in the first year from early sowings, and June to August in the following year from outdoor sowings.