Centaurea nigra
common knapweed
This native grassland perennial can be found colonising meadows, scrub, and woodland edges. A tough (and often variable wildflower), it will typically produce a whorl of brown/black bracts, which is topped with a light purple-pink (occasionally white) inflorescence. Definitely a worthy contender for a wildlife-friendly garden where birds and bees are welcomed, it will freely self-seed once settled into a good spot.
How to care for Centaurea nigra:
Wild flowers prefer poor soils, so do not apply fertiliser. Deadhead regularly to prolong flowering. In autumn, cut the faded flowerheads down to the ground and compost the dead stems.
Sowing instructions:
Surface-sow seeds in trays filled with good quality compost, water and place in a cold frame or greenhouse. Pot on when they have put on their first true leaves and harden off before planting out after the frosts have passed. Alternatively sow directly in late spring or early summer, and thin out to 30cm as they grow. Seeds sown in autumn and over-wintered in a cold frame will produce plants that will flower earlier in the year than those sown in spring.
Flowering period:
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
Eventual height:
0.7m
Eventual spread:
0.5m
Position:
Full sun
Rate of growth:
Fast-growing
Soil:
Moderately fertile, moist, well-drained soil
Hardiness:
Fully hardy
9cm pot
£7.99
In stock
(shipped within 2-3 working days)
(shipped within 2-3 working days)
3 × 9cm pots
£18.99
£6.33 each
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(shipped within 2-3 working days)
6 × 9cm pots
£34.99
£5.83 each
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(shipped within 2-3 working days)
approx 20 seeds
£2.99
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(shipped within 2-3 working days)
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