Verbena bonariensis (also called Argentinian vervain and purple top)
Tall clump forming herbaceous perennial with domed heads of lilac florets. Useful for flower beds and borders, gravel gardens, prairie and wildlife planting. Provides attractive and non-intrusive height in the borders. Good wildlife plant; flowers attract bees and butterflies during the day, whilst scent becomes stronger after dark, attracting night insects like moths.
Lilac flowers from mid summer to late autumn.
Tall, open habit. H: up to 2m.
Stems - slender, square, ridged; slightly hairy.
Long, serrated leaves with no petiole (leaf stalk).
Clustered, lightly scented, flat/domed headed flowers in lilac.
Sunny. Stands well against wind.
Well drained, light.
Hardy down to -5c, though will overwinter more successfully in well drained soil.
Cut back old blooms to promote more flowers. Generally stands well in wind, but sometimes plants need support.
From seed sown in early spring, with heat. Will self-seed in well drained soil.
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