Centaurea Nigra | Common Knapweed

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. Wildflowers prefer poorer soils, so do not use a fertiliser. Deadhead regularly to prolong flowering. In autumn cut the faded flower-heads down to the ground and compost the dead stems. 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. Sow: September - November or March - May Approximate quantity: 20 seeds