Cytisus x boskoopii 'Boskoop Ruby'

About this cultivar:

Cytisus x boskoopii 'Boskoop Ruby' is a compact deciduous shrub of rounded habit replete with ravishing ruby red flowers on upright shoots in late spring and early summer.

Has the Royal Horticultural Society Award of Garden Merit, but can't find any notes about it. Strange as it is not so rare a shrub, and perhaps the best Cytisus! But after a lot of deep, difficult, thinking I can conclude that perhaps it has something to do with Boskoop, Holland.

• Position: Full sun, partial shade (better in full sun)
• Soil: Almost any soil - Grows well in Ballyrobert
• Flowers: May, June, July, August
  
• Other features: Royal Horticultural Society Award of Garden Merit (RHS AGM), Bees, Butterflies, and Bugs
• Hardiness: Fully Hardy - Grows well in Ballyrobert, H5 - Hardy in most places throughout the UK even in severe winters (-15 to -10°C)
• Habit: Bushy
• Foliage: Deciduous
• Height: 100 to 120 cm  ( 3.5 - 4 ft)
• Spread: 120 to 150 cm  ( 4 - 5 ft)
• Time to full growth: 5 to 10 years
• Plant type: Herbaceous Perennial, Shrub
• Colour: Pink, green, red
• Goes well with: Wall, Fence, border, informal hedge

About this genus:

Cytisus is a genus of about 50 species of flowering plants in the Legume/Pea family (Fabaceae), native to Europe, western Asia and North Africa. The genus name comes from the Greek word kytisos used by the Greeks for several kinds of woody legumes. Commonly called brooms, they are shrubs producing masses of brightly coloured, often fragrant, pea-like flowers. Usually the flowers are white or yellow.

Commonly found on open sites (typically scrub and heathland) they are often thought of as drought resistant plants, but will grow almost anywhere. Put it this way, they are the closely related to gorse.

Lifecycle wise they are much like Ceanothus - they may be short-lived and have a tendency to decline significantly after 5 years, and don’t respond to pruning. However! HOWEVER! They grow fast, flower profusely, and for a long time. An explosion of flowers that insects love! Depending on the species they are versatile and can look particularly good grown or trained against a sunny, sheltered wall, but can also be used as border plants, informal hedges and ground cover.