Persicaria amplexicaulis Inverleith - Mountain Fleece

The Persicaria amplexicaulis 'Inverleith' is currently the smallest of all perennial knotweeds and as such a variety whose vigor is easily controlled. Therefore, it is ideal for borders and small spaces. This pretty variety with dark green foliage and a flexible habit produces, in the second part of summer, a quantity of short spikes of a delightful purplish pink to raspberry red. Very hardy, it is easily grown in good garden soil that retains moisture, even clayey, in a sunny or semi-shady position.

Persicaria or Polygonum amplexicaule 'Inverleith' is a plant from the family of polygonaceae. It is a horticultural selection appreciated for its moderate growth, derived from a botanical species native to the Himalayas. This rhizomatous perennial plant, more or less deciduous or semi-evergreen, forms a clump that will not exceed 40 cm (16in) in height when flowering, with a spread of 50 cm (20in). It spreads rather quickly, depending on the richness of the soil, and can eventually form a beautiful low ground cover after several years. Very floriferous, this knotweed produces at the axil of the leaves, located at the end of reddish stems, numerous very short and open spikes, composed of a multitude of small red flowers that turn more purplish pink when they open, with a matte finish. The flowering is continuous from July to September, if the soil does not dry out too much. The leaves, borne by sturdy stems, are wide and lanceolate, measuring 6-8 cm (2-3in) long, stem-clasping, dark green and vibrant, villous on the underside, and often become purple in autumn.

Like astrantias, knotweeds are very popular plants, thanks to their good adaptation to cold and humid climates and their sleek appearance that suits contemporary gardens as well as rustic and romantic flowerbeds. They form, along with grasses such as Miscanthus and Panicum, stunning autumn scenes. Thanks to its low and spreading habit, Polygonum 'Inverleith' can be used as an edging plant for paths or flowerbeds, in semi-shady areas of the garden. Provide it with sturdy companions that it won't smother. It likes rich and heavy, even very moist, soils and can be grown independently on sunny banks of a pond, along a sunken path, or in a cool understory at the base of trees. Asters, echinaceas, Stachys monierii 'Hummelo' and Sanguisorba 'Red Thunder', for example, are good companions for knotweeds, in the garden or in bouquets as they also flower until autumn.