Cosmos.--Pretty plants, the flowers resembling a single Dahlia. They
are mostly hardy, but some need protection. The annuals should
be raised on a hotbed in February and be planted out in May. The
perennials, too, are brought forward in heat. Some flower in June,
others in September. Height, 1 ft. to 3 ft.
Cotoneaster.--Evergreen shrubs which will grow in any soil and are
easily increased by layers. C. Hookeriana attains the dimensions of
small trees, and produces a profusion of white flowers and bright
crimson berries. C. Simonsii is largely used as a hedge. Height, 6 ft.
to 8 ft. C. Rupestris is a small-leaved, prostrate perennial species,
bearing white flowers from May to August, followed by red berries.
Height, 3 in.
Cotyledon Chrysantha (Umbilicus).--A choice Alpine succulent which
thrives in a sandy loam, or in well-drained pots of the same soil. It
flowers from May to August, and is multiplied by cuttings, which must
be left to dry for a few days in a sunny place. Flowers are produced
from May to August. Height, 3 in.
Cowslips.--Well-known hardy perennials. These require the same
treatment as Primulas. Plant in a mixture of loam and peat, and divide
as soon as the bloom has died off. Height, 6 in.
Cowslips, Cape.--See "Lachenalia."
Crambe Cordifolia (Tournefort, or Sea Cabbage).--This hardy
herbaceous plant is suitable for a wild garden. It likes a good, rich
soil, and is easily increased by seed or division. August is its
flowering period. Height, 3 ft.
Crane's Bill.--See "Geranium Argentium."
Crataegus Pyracantha (Fire Thorn).--This hardy, ornamental shrub
will grow in any soil. It should be planted early in spring on a south
or south-west wall, and may be increased by seeds, by budding, or by
grafting. The profuse brilliant orange-coloured berries of the C.
Lelandii (Mespilus) ensures it a place on walls and trellises. A sunny
position gives best results. Prune in March.
Creeping Jenny.--See "Lysimachia Nummularia."
Crepis (Hawkweed).--An interesting hardy annual. It merely requires
sowing in spring, and will grow in any soil. The flowers are produced
in June. Height, 1 ft.
Cress.--Sow at intervals of a week from March to September in the open
ground, and during the winter months in frames. A shady position is
most suitable. By these frequent sowings, and by often cutting over
such as readily renew a bottom growth, a constant succession of tender
shoots is obtained.
Crocus.--Among our earliest spring flowers. These will grow in any