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This upright, branched perennial produces tightly packed clusters of lilac-purple flowers on tall stiff stems during mid-summer and early autumn. Verbena bonariensis has dark green, thin, lance-shaped leaves but few are produced. Being slightly tender, the rootstock of this plant needs mulching during winter. Verbena bonariensis is usually short-lived but does self-seed freely. Perfect for a sheltered sunny well-drained spot its open transparent shape means that it can easily be used at the front or middle of the border despite its height.

• Soil: moderately fertile moist well-drained soil
• Garden Care: In cold conditions Verbena bonariensis can suffer dieback if cut back in autumn so it's best to leave the plant until spring and cut back the old growth when you see the new shoots emerging at the base. Also it's a good idea to mulch around the base of the plant with a deep dry mulch in winter to help protect the plant. Where the plant is grown in partial shade the stems may need to be supported - if this is necessary use natural materials such as brushwood or twiggy pea-sticks.