Black Knight Delphinium Plants

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Misc Wildlife Value
Shade Full Sun, Partial Shade
Area Frost Pockets, Scotland & The North
Soil Good, Well Drained
Colour Purple
Type Pot Grown
Also Good Repeat Flowering
Flowering Jun, Jul

Delphinium Pacific Giants Black Knight

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SIZES 1-2 3-910+
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Pacific Giants Black Knight delphinium

Black Knight is a stunning plant with its lofty flower spikes, up to 1.7m, stacked from top to bottom with double blooms in a regal shade of purple. Each flower on this delphinium is a little trumpet, black at the centre, and the leaves, further down, are glossy, deeply divided and vine-like. The buds come in May, opening in June and continuing through to July. Cut back the spent flower stems and you'll be rewarded with a second flush of smaller flowers in late summer. It makes a lovely cut flower, lending a stately, regal quality to indoor arrangements. Absolutely one of the best of our delphiniums.

In the garden

Delphiniums need sun, with well-drained fertile soil. So dig in plenty of compost when planting. And don't plant too early in the season – give them time to bulk up before you plant them out from their pots or they can become ruined by ravenous slugs and snails. And when you do plant them out, it's worth placing slug or snail traps nearby, or surrounding them with a barrier of broken shells, just to make sure. Obviously they're tall so position your delphiniums towards the back of a south- or west-facing border, where they'll grow up to create the most wonderful vertical accents, contrasting handsomely with the rounded, spreading and fan shapes of your other border perennials. You'll need to stake them in late spring to protect from wind damage later on; do it any later and you'll risk not being able to get at them through the foliage and tall growth. It's a good idea to feed every 2-3 weeks in the flowering season. And cut back individual spent flower stems. Do these two things and you'll be rewarded with a second, less dramatic, flowering by the end of summer.

A true classic among cottage garden perennials, delphiniums combine beautifully with roses (try a pink one with a little blue in it, such as Gloire de France for a heavenly combo), euphorbias, lavender, lady's mantle, achillea, anthemis and a host of other colourful border perennials.


  • Colour: dark purple with black centres
  • Flowering: Jun-Jul
  • Foliage: dark green, deeply divided and vine-like
  • Height: 1.7m
  • Spread: 75cm
  • Spacing: 60cm
  • Position: full sun
  • Soil: well-drained, fertile

Fun fact

Delphinium is named after the Greek, delphin, for dolphin. Look closely and you might just spot the individual flowers' resemblance to this fabulous sea creature.

  • Small Box

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Bareroot planting is best done between October and April
Bareroot and potted - what's the difference?

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