Laburnum Laburnocytisus 'Adamii'

Adam's laburnum is in the pea or Fabaceae family and is an unusual hybrid, a graft-chimaera between 2 species, a laburnum (L. anagroides), and a broom (Chamaecytisus purpureus).

A graft-chimaera is not a true hybrid but a mixture of cells, each with the genotype of one of its parents, so the term "hybrid" is discouraged in this case. The plant thus has shoots of both species and some of a mixed species.

• Some branches have long (20–30 cm) racemes of yellow laburnum flowers, while others produce dense clusters of purple broom flowers. Remarkably, most branches will also produce coppery-pink flowers on short (8–15 cm) racemes, which are midway between the two parents; the leaves on these shoots are also intermediate.
• Most of the tree's branches resemble the laburnum in their foliage, which has three leaflets, 3–6 cm long, yet also with dense clusters of broom-like shoots, also with three leaflets, but only 1 cm long and a darker green.