Red-hot Poker.—See “Tritoma.”
Red Scale.—See “Scale.”
Red Spiders.—These troublesome pests which appear in the heat of summer, may be got rid of by constantly syringing the plants attacked, and by occasionally washing the walls, etc., with lime or sulphur.
Retinospora Filifera.—A large-growing, hardy evergreen shrub. It may be grown in any light soil, and increased by seed, or by cuttings planted under glass in the shade. It flowers in May.
Rhamnus (Buckthorn).—Fine evergreen shrubs, of hardy habit and quick growth. They may be grown in any soil, but prefer a sheltered situation, and are very suitable for planting near the sea. R. Latifolius has handsome broad leaves. Some, such as R. Alaternus and R. Catharticus, attain large proportions, the former reaching 30 ft. and the latter 10 ft. in height. They may be propagated by layers or by seed.
Rheum Palmatum.—This species of rhubarb makes an effective plant for the back portion of a border. It does well in rich loam, flowering in June, and is increased by dividing the root. Height, 5 ft.
Rhodanthe (Swan River Everlasting).—These beautiful everlasting flowers are half-hardy annuals and are suitable for beds or ribbons, and make most graceful plants for pot culture, placing four plants in a 5-in. pot. They thrive best in fibrous peat or a rich, light soil, and prefer a warm situation. Used largely for winter bouquets, and are perfect gems for pot culture. A succession of bloom may be obtained by sowings made in August, October, and March. The temperature of the seed-pots should be kept at from 60 to 70 degrees, and the soil kept constantly damp with water of the same heat. After potting the seedlings remove them to a cooler house and keep them near the glass. Those sown in March may be planted in the open in June, where they will flower in autumn. Height, 1 ft.