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Home>Flowers, Plants & Shrubs>Garden Plants>Flowers, Plants & Shrubs>Perennial & Biennial Plants>Border Perennials
Popular 12 others are looking at this right now
Centaurea nigraCommon Knapweed, Wildflower, Perennial Cornflower
Hardy Perennial
What is Hardy Perennial?
A plant that lives for more than two years.
Capable of withstanding outdoor winter temperatures down to -15C.
A plant that lives for more than two years.
Capable of withstanding outdoor winter temperatures down to -15C.
£19.99
Small bright purple flowers
Flowers from July to September
Loved by pollinators
Delivery Information
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Height Up to 75cm (30in)
Spread Up to 50cm (20in)
Hardy Perennial
cottage gardenswildlife gardenslow maintenance garden
full sun
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Description
How to Grow
Knapweed makes a fabulous low-maintenance perennial, happy even in poor soils and hardy from one end of the UK to the other! This British wildflower will light up your garden borders with its glowing pink-purple blooms from June to September and is particularly attractive to butterflies. Common knapweed is a fabulous addition to informal borders, cottage gardens and wildlife gardens. Height: 75cm (30"). Spread: 50cm (20").
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1 x 1 Litre Potted Plant (KA4920)
Plant in a position with full sun. Knapweed is drought tolerant once established and will happily tolerate almost any soil, except those that are excessively waterlogged.
More Info Water knapweed plants regularly until fully established. This plant will self-seed freely. If seedlings are not wanted, deadhead stems of knapweed flowers as the blooms fade. In autumn, cut back old stems to just above ground level to make way for new growth in the spring.
Delivery
Seeds and garden supplies will normally be delivered within the time period stated against each product as detailed above. Plants, bulbs, corms, tubers, shrubs, trees, potatoes, etc. are delivered at the appropriate time for planting or potting on. Delivery times will be stated on the product page above, or in your order acknowledgement page and email.
Orders for packets of seed incur a delivery charge of £2.99.
Orders which include any other products will incur a delivery charge of £6.99.
Where an order includes both packets of seeds and other products, a maximum delivery charge of £7.99 will apply - regardless of the number of items ordered.
Large items may incur a higher delivery charge - this will be displayed in your shopping basket.
Please see our Delivery page for further details, and more information on different charges that may apply to certain destinations.
For more information on how we send your plants please visit our Helpful Guide on plant sizes.
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