Thalictrum delavayi Hewitts double - Meadow-rue

Thalictrum delavayi 'Hewitt's Double' is a very pretty form of meadow rue with double flowers in a lovely mauve colour. It is a variety of rather modest stature, which is as much appreciated for its finely cut and chiseled bluish-green foliage as for its long summer to autumn flowering in a mist of small flowers as light as those of baby's breath. Truly graceful, this perennial is also a hardy plant that takes some time to establish. It will work beautifully in semi-shaded borders, in moist soil, protected from the wind that can break its thin stems.

Thalictrum 'Hewitt's Double' is a horticultural selection derived from Thalictrum delavayi, also known as Thalictrum dipterocarpum, a rhizomatous perennial plant of the buttercup family. This species is native to the Himalayan region, from eastern Tibet to western China. It is found in the wild at high altitudes, in forests, scrublands, on grassy slopes, not far from watercourses. This variety 'Hewitt's Double' is a clone with double flowers. The above-ground vegetation, which is deciduous, emerges from the ground in spring and dries up in autumn. The plant has an upright and erect habit, forming a bushy clump, from which stems rise, reaching a height of about 1 m (3ft), sometimes 1.20 m (4ft), with a width of 30 to 40 cm (12 to 16in). Its foliage, glaucous green on top, bluish underneath, finely cut and very light, resembles that of a columbine; it is composed of leaves 15 to 35 cm (6 to 14in) long, pinnate or ternate, with entire or trilobed leaflets. From July-August to October, large panicles appear, terminal and axillary, well-branched, filled with numerous small mauve petaloid stamens. This flowering attracts bumblebees, bees, and hoverflies. Not liking the competition of nearby roots, a planting distance of 40 cm (16in) around its base should be respected. Thalictrums, which are rather slow to establish, will become more and more beautiful over time.

Thalictrum delavayi 'Hewitt's Double' provides the same ornamental function as panicled baby's breath, but unlike them, it prefers damp and slightly shaded areas of the garden. With its size, delicate and elegant bluish columbine-like foliage, and airy appearance, it will be perfect for adding height and lightness to borders. Its transparent silhouette allows it to be planted at the front of borders to create a beautiful effect. It will be particularly effective in contrast with less delicate shade perennials (Rodgersia, Hosta), as well as on the edges of shrub borders. It will naturally find its place alongside Hydrangeas, shrub or climbing Roses, Fuchsias, Japanese Anemones, Bearded Irises, Bellflowers, Snowberries, Ferns, Hellebores, Foxgloves, and silver candles.