Carrots.—­To grow them to perfection carrots require a deep, rich, sandy soil, which has been thoroughly trenched and manured the previous autumn.  For the main crop the seed should be sown in March, either broadcast or in rows 18 in. apart.  A calm day must be chosen for sowing, as the seed is very light and liable to be blown about.  It has also a tendency to hang together, to obviate which it is generally rubbed into some light soil or sand previously to being scattered.  Thin out to a distance of from 4 to 7 in., according to the kind grown.  For early use the French Horn may be sown on a hotbed in January and February.  Keep the surface of the ground well open with the hoe.

Cassia Corymbosa.—­This stove shrub is an evergreen.  It should be grown in a mixture of loam and peat, and may be increased by cuttings planted in sand under glass in a little heat.  It flowers in July.  Height, 3 ft.

Castor Oil Plants.—­See “Ricinus.”

Catananche.—­Pretty hardy biennials that will grow in almost any soil, and may be increased by seed or division.  They bloom in August.  Height, 21/2 ft. to 3 ft.

Catchfly.—­See “Silene.”

Cathcartia Villosa.—­A beautiful Himalayan poppy, possessing a rich, soft, hairy foliage and yellow flowers, borne in succession from June to September.  Any light, rich soil suits it, but it requires a sheltered position.  It is propagated by seeds sown in spring.  Height, 11/2 ft.

Cauliflowers.—­Sow thinly in pans or shallow boxes early in February and March on a gentle bottom-heat.  Make a larger and the main sowing in the open ground in March, April, and May for autumn cutting.  A sowing should also be made in August for spring and summer use.  These latter should be pricked into a frame or under a hand-glass during the winter, and in spring planted out so as to stand 30 in. apart.  When the heads appear break some of the large leaves down over them to afford protection, and during the whole of their growth pour plenty of water round the stems in dry weather.  They require a thoroughly rich and well-tilled soil to grow them to perfection.

Ceanothus.—­A genus of handsome and ornamental evergreen shrubs.  They are free-flowering and suitable for the conservatory or outdoor decoration if placed in warm situations.  They flourish best in peat and loam, and are increased by cuttings planted in sand and subjected to gentle heat.  Height, 3 ft. to 6 ft.

Cedronella.—­Ornamental hardy perennials; will grow in any soil, but require a little protection in the winter.  They produce their deep purple flowers in June.  Height, 3 ft.

Cedrus Deodora.—­A beautiful and graceful conifer, its arched branches being thickly set with long grey-coloured or whitish-green leaves.  In its young stage it makes an exquisite specimen for the lawn.  It is the best of all the Cedars for such a purpose.  The usual method of propagating it is by grafting it on to the common Larch.