For many people, April would not be the same without Forsythia creating its bright splashes of yellow in the suburban landscape. For others, however, the double yellow button flowers of Kerria japonica 'Pleniflora' are far more satisfying and this shrub has attractive green cane-like shoots as a bonus. It is a tall-growing suckering shrub up to юА(зт) tall and makes a loose mound of arching stems where space permits; otherwise it is normally grown against a wall. The single-flowered type is only half that height.Blue is a colour which contrasts effectively with yellow and although there is a preponderance of yellow flowers over blue in spring the latter colour is well represented by a large number of the ceanothus. For gardens in mild areas and where space will permit the planting of a large shrub, the most impressive is undoubtedly C. arboreus Trewithen Blue', whose comparatively large evergreen leaves are almost hidden in spring by the dense panicles of deep blue flowers. When thriving it will attain 10 to 15(3 to 4.5m) or more eventually and then is a spectacular sight. c. thyrsiflom, meanwhile, has paler blue flowers and smaller leaves and is known for its comparative hardiness. It can attain ioft(3m) or more when happy and produce its flowers from May into June. There are several evergreen hybrids of medium to large size which, in warm gardens certainly, will produce a bold display of bright blue flowers. They include C.xlobbianus, c. 'Cascade', c. 'Southmead', c. 'Delight' and c. 'Italian Skies'. Attractive foliage and flower are important assets for a garden shrub and when both are combined they ensure for that shrub a special place in the garden. Paeonia lutea var. ludlowii is one such and although it requires plenty of space in which to develop its full potential those gardens with space enough to accommodate it should do so. The large boldly-lobed leaves are handsome in themselves and the cup-shaped, yellow flowers-like large kingcups-are borne on long stalks among the leaves in May. Although tolerant of some shade this peony flowers best in a well-drained, even dry, sunny site. Some of the amelanchiers are dual-purpose shrubs with flowers and autumn colour. The most spectacular perhaps is Amelanchier lamarckii, which has been referred to as A. confusa, A. arborea and, most frequently, as A. canadensis. It is still found described under the last-mentioned name in most British nursery catalogues. In April the naked branches of this large bushy shrub or small tree are covered as if with snow as each shoot tip and spur produces a short raceme of white flowers. Again, in autumn, the shrub attracts attention with its brilliant orange and crimson tints. Deutzia pulchra is possibly the most impressive of its clan and one of the earliest to flower. It will reach 8 to ioft(2.5 to 3m) when thriving and has attractive exfoliating, warm orange-brown bark.