may be cured by sprinkling the leaves with sulphur while dew is on
them.
Rose of Heaven.--See "Viscaria Coeli Rosa."
Rose of Sharon.--See "Hibiscus Syriacus."
Rubus.--See "Blackberries."
Rudbeckia (Cone Flower.)--Hardy annuals yielding yellow flowers in
July. They are readily grown from seed sown early in spring, and will
grow in any garden soil, but naturally succeed best in deeply-worked,
well-manured ground. They may be increased by division in October or
November, as well as in spring-time. Height, 3 ft.
Ruscus Aculeatus (Butchers Broom).--A hardy evergreen shrub which
thrives in any rich soil, and may be increased by division of the
root. Height, 1 ft.
Ruta Graveolens.--This hardy evergreen shrub is a species of Rue.
It enjoys a good, rich soil, in which it flowers freely in August.
Cuttings may be struck under a hand-glass. Height, 3 ft.
Ruta Patavina (Rue of Padua).--For rock-work this hardy perennial is
very useful. It likes a dry yet rich and light soil. At midsummer it
produces an abundance of greenish-yellow flowers. It can be raised
from seed, or cuttings may be struck under a hand-glass. Height, 6 in.
S
Saffron, Spring.--See "Bulbocodium."
Sage.--This useful herb likes a rich, light soil, and is propagated by
division of the root, by cuttings, or by seed.
Saintpaulia Ionantha.--The leaves of this plant spread themselves
laterally just over the soil, forming a rosette, in the centre of
which spring up large violet-like flowers. It is a continuous bloomer.
A rather light, rich soil or vegetable mould suits it best. The seed,
which is very minute, should be sown early in spring, in gentle heat:
to prevent it being washed away, the pots may stand up to the rims in
water for a while when the ground wants moisture. Height, 1 ft.
St. John's Wort.--See "Hypericum."
Salix Reticulata.--A dwarf creeping plant whose dark green leaves
eminently fit it for the rock-work or carpet bedding. It will grow in
any soil, but prefers a moist one, and produces unattractive brown
flowers in September. Propagated in spring by detaching rooted
portions from the parent plant and planting them in moist, sandy loam.
Height, 2 in.