raspberry

a plant of the genus Rubus of the family Rosaceae. It is a deciduous subshrub measuring 1-3 m tall. The underground part of the plant is perennial and consists of a rootstock and numerous lateral roots that form suckers. The aboveground part consists of green, red, or violet biennial or annual canes with spines varying in size and shape. The leaves are ternate or pinnately compound; less frequently, they are palmate. The white, bisexual flowers are in racemes or corymbs. The fruit (berry) is a red, yellow, or purple-black compound drupe, which can be easily separated from its torus (in contrast to blackberries). Flowering occurs in May and June (25-30 days), and the berries ripen in July.

There are more than 120 known species of raspberries, found primarily in the temperate and subtropical regions of Asia, America, and Europe. Raspberries are cultivated in the USSR, the United States, and Europe. Their range of distribution extends to 62°-64° N lat. In the USSR, raspberries are cultivated mainly in Moscow, Leningrad, Kursk, and Voronezh oblasts, in the Ukrainian SSR, in the Byelorussian SSR, in the Ural region, and in some regions of Siberia. Raspberries, which have been known since the third century B.C., have been cultivated since the fourth century A.D. Varieties appeared only in the 16th and 17th centuries; they have been cultivated in what is now the USSR since the 19th century. Cultivated varieties of raspberries have been developed from the European red raspberry (Rubus idaeus), the blackcap (R. occidentalis), the wild red raspberry (R. strigosus), and R. neglectus (a hybrid of R. occidentalis and R. strigosus).

The fruits, or raspberries, depending on the variety, contain 5.7-11.5 percent sugars, 1-2 percent organic acids, 9.1-44 mg of vitamin C per 100 g of fruit, vitamin B, carotene (provitamin A), and aromatics. They are eaten fresh or processed (jam, juice, syrup, wine). A decoction from the dried fruits is used as a diaphoretic; raspberries are also used fresh in diaphoretic preparations (teas). Syrups from the fruits are used to improve the flavor of medicines. The fruit yield is up to 10 tons per hectare (ha).

In the USSR more than 70 varieties of raspberries have been regionalized, the most common being English, Vislukha, Volzhanka, Herbert, Kaliningrad, Kaluzhanka, King, Crimson Mammoth, Cuthbert, Marlboro, Novost’ Kuz’mina, Turner, Usanka, and Progress. There are remontant varieties (English), which bear fruit twice a year, in the spring and autumn. Raspberries are propagated primarily from root suckers, root cuttings, and division of shrubs; seeds are used only when developing new varieties.

Raspberries should be planted on level or gently sloping land that is protected from prevailing cold winds. The soil must be fertile, loose, well-drained, and sufficiently moist. Raspberry shrubs will not grow on heavy, clayey sierozems. The groundwater must be no closer than 1.5 m to the soil surface. Raspberries are planted in rows that usually extend from north to south and are 2.5-3 m apart. The plants are spaced 0.75 m. apart. Raspberry plantings are made in the spring before the opening of the buds or in the fall after leaf fall. Before planting, 80-90 tons/ha of manure or compost are applied to the soil. After planting, the shrubs are watered (2-3 liters per shrub), and the soil is mulched with manure or humus.

Care includes stirring and loosening the soil, weeding, annually applying organic and mineral fertilizers, pruning the old fruiting canes in the fall, and tying the shrubs to trellises or stakes. In the fall, nine or ten of the strongest annual shoots are left on the shrub; they are cut back to a length of 1.3-1.5 m. In the winter the shoots of two neighboring raspberry shrubs are bent toward one another and tied. In the spring, before interrow tillage, the shrubs are untied.

The principal insect pests of raspberry plants are the raspberry beetle Byturus tomentosus, the strawberry weevil Anthonomus rubi, aphids, clearwings, and the Chortophia dentiens. Diseases of raspberry plants are anthracnose, rust, gray mold (causative agent Botrytis cinerea), and canker (Bacterium tumefaciens). Great damage is caused by dodder, which retards the growth and development of the plants.