PIPTANTHUS.

PIPTANTHUS NEPALENSIS (syn Baptisia nepalensis).—­Evergreen Laburnum.  Temperate Himalaya, 1821.  A handsome, half-hardy shrub, of often fully 10 feet high, with trifoliolate, evergreen leaves, and terminal racemes of large yellow flowers.  In the south and west of England and Ireland it does well, and only receives injury during very severe winters.  Planted either as a single specimen, or in clumps of three or five, the evergreen Laburnum has a pleasing effect, whether with its bright, glossy-green leaves, or abundance of showy flowers.  It is of somewhat erect growth, with stout branches and plenty of shoots.  Propagated from seed, which it ripens abundantly in this country.

PITTOSPORUM.

PITTOSPORUM TOBIRA.—­Japan, 1804.  This forms a neat, evergreen shrub, with deep green, leathery leaves, and clusters of white, fragrant flowers, each about an inch in diameter.  It is hardy in the more favoured parts of the south and west of England, where it makes a reliable seaside shrub.

P. UNDULATUM, from Australia (1789), is also hardy against a wall, but cannot be depended upon generally.  It is a neat shrub, with wavy leaves, that are rendered conspicuous by the dark midribs.  They grow well in any good garden soil.

PLAGIANTHUS.

PLAGIANTHUS LYALLI, a native of New Zealand (1871), and a member of the Mallow family, is a free-flowering and beautiful shrub, but one that cannot be recommended for general planting in this country.  At Kew it does well and flowers freely on an east wall.  The flowers are snow-white, with golden-yellow anthers, and produced on the ends of the last season’s branchlets during June and July.  The flower-stalks, being fully 2 inches long, give to the flowers a very graceful appearance.  In this country the leaves are frequently retained till spring.

P. LAMPENI.—­Van Dieman’s Land, 1833.  This is about equally hardy with the former, and produces a great abundance of sweetly-scented flowers.

P. PULCHELLUS (syn Sida pulchella).—­Australia and Tasmania.  Another half-hardy species, which bears, even in a young state, an abundance of rather small, whitish flowers.

POLYGALA.

POLYGALA CHAMAEBUXUS.—­Bastard Box.  A neat little shrubby plant, with small ovate, coriaceous leaves, and fragrant yellow and cream flowers.  P. chamaebuxus purpureus differs in bearing rich reddish-purple flowers, and is one of the most showy and beautiful of rock plants.  They are natives of Europe (1658), and grow best in vegetable mould.

POTENTILLA.

POTENTILLA FRUTICOSA.—­Northern Hemisphere (Britain).  An indigenous shrub that grows about a yard high, with pinnate leaves and golden flowers.  It is a most persistent blooming plant, as often for four months, beginning in June, the flowers are produced freely in succession.  It delights to grow in a strong soil, and, being of low, sturdy growth, does well for the outer line of the shrubbery.