Synonyms: Kew broom
Cytisus × kewensis Bean — a species of deciduous plants from the family Fabaceae (Fabaceae). A chance interspecific hybrid Cytisus ardoini E.Fourn. × Cytisus multiflorus (L’Her.) Sweet. It was discovered in 1891 in the Kew Botanic Garden in Surrey (England). It was first described by the British botanist and curator of the Royal Botanic Gardens, Kew, William Jackson Bean in 1896 in the book «Kew Hand-List Trees & Shrubs» In 1993 the hybrid was awarded the prestigious «Award of Garden Merit». In cultivation since 1900.
A dwarf deciduous shrub 0.3 m in height and 2 m in width. Branches are prostrate and pendulous, numerous, thin, grey-green in color, glabrous. Grows slowly.
Leaves are trifoliate, petiolate. Leaflets narrow, linear-elongated, hairy, acute, grey-green in color.
Flowers occur singly, in pairs or in groups of 3 , in the leaf axils along the full length of the shoots. The corolla is papilionaceous, pale yellow or whitish-cream in color. The standard 1,2-1,4 cm in length, rounded. Calyx brownish-green, glabrous, tubular-campanulate. Blooms in May–June, for a long time and abundantly.
Fruits — narrowly oblong, flattened pods with several seeds inside.
Cultivars: ’Niki’, ’Luna’
Hardiness zone: zone 5-8 (-23°C).
Location: very light-demanding. The best place to plant — an open site with southern exposure, preferably sheltered from cold winds. Not recommended to plant near ponds with fish.
Pruning: after flowering it is recommended to cut back the faded shoots by half, not cutting into old wood.
Propagation: by seed, sown in spring after a 2-month stratification, and also by green cuttings in summer. Cultivars can be propagated by grafting onto Laburnum.
Soil: drought-tolerant, does not tolerate prolonged water stagnation or overwatering. Does not like clay soil. Not demanding of soil fertility; can grow on any garden soil, including very poor ones. Prefers slightly acidic soil. Optimal soil pH 6.5 — 7.5.
Planting: soil mixture — one part sand and the other part turf soil, peat compost or humus; a complete mineral fertilizer or Kemira-Universal (120 g per 1 m2) can be added. Does not like transplanting. Recommended spacing between plants — 30-50 cm. The root collar at ground level. Drainage is essential (on heavy soils — layer 15-20 cm, on light soils — 10 cm). After planting mulch the tree circle with soil or peat to a depth of 3-5 cm.
Care: does not require watering. For better flowering it is recommended to feed the plant twice a year — first in spring, second — before flowering. In spring apply urea (20 — 30 g per 10 l of water), in summer — 60 g granular superphosphate and 30 g potassium sulfate. To stimulate growth wood ash can be applied — 200 g under each bush. Loosening not deeper than 8-12 cm.
Diseases: Powdery mildew (treatment of dormant buds with copper sulfate (5%), in summer regular treatment with Fundazol, copper-soap solution, colloidal sulfur (0.8%) alternately), Black spot (treatment of dormant buds with iron or copper sulfate; in summer spraying with Fundazol, polikarbatsin (0.2 — 0.4%), copper oxychloride (1%), captan (0.5%), Bordeaux mixture (1%)).
Pests: broom moth (spraying with chlorophos (0.2%)), broom geometer (treatment with organophosphorus or bacterial insecticides).
Companion plants: Deutzia, birches, weigelas, Philadelphus (mock orange), heather.
Uses: a good nectar source. One of the most popular dwarf brooms in Europe. Used in rock gardens and parterres.
