Heuchera.--Very neat, but not showy, hardy American perennials. They
may be grown in any ordinary light garden soil, are increased by
dividing the root, and bloom in May. Height, 1 ft. to 2 ft.
Hibbertia Dentata.--An evergreen twining plant, requiring a greenhouse
for its cultivation and a soil of sandy loam and peat. It flowers in
July, and is increased by cuttings taken in spring or summer and kept
under glass. Height, 6 ft.
Hibiscus Africanus.--A handsome hardy annual Mallow. Sow in March
in slight heat, and plant out in May 10 in. apart. Grows best in a
mixture of loam and peat. Blooms in June. Height, 2 ft.
Hibiscus Syriacus (_Rose of Sharon_).--A hardy, deciduous,
autumn-flowering shrub, which will grow in common soil, and may be
propagated by seeds, layers, or cuttings planted under glass. Height,
6 ft.
Hieracium (_Hawkweed_).--A free-growing hardy perennial, suitable for
a sunny bank or border. It is not particular as to soil. From June to
September it produces orange-brown flowers. It grows freely from seed,
and the roots bear division. Height, 1-1/2 ft.