Culture
Best grown in organically rich, slightly acidic, moist but well-drained soils in full sun to part shade. Intolerant of wet soils which can cause root rot. When grown for harvest of its raspberry fruits, raised beds should be considered in areas with heavy clay soils. Prune out fruiting canes of both summer and everbearing cultivars in summer immediately after fruiting and any non-fruiting canes that exhibit weakness or disease. new shoot will develop and, everbearing cultivars will produce fruit on the tips of these shoots. In late winter, remove any canes damaged by winter and thin, as needed, the remaining canes. Cut back the tips of everbearers that fruited last fall but leave the rest of cane for summer fruiting. Promptly remove excess new plants and suckers to control spread. Stems may root where they touch the ground. Plants adapt to a variety of soils, preferring those that are reasonably fertile and of medium and consistent moisture. Most do well in sun, but a few prefer light shade. Pruning is essential in order to keep plants well-maintained. It is generally best to prune out old, summer-bearing canes as soon as fruiting is over for purposes of encouraging the production of new canes. Raspberry roots are perennial but the leaf- and fruit-bearing canes are biennial, each cane living only two growing seasons before dying. In the wild, plants spread by suckers, stolons, rhizomes or root crowns to rapidly colonize certain areas, particularly disturbed areas such as those left after logging or forest fires. If grown for ornamental reasons, raspberries are best located in areas where they can naturalize.
Noteworthy Characteristics
Rubus idaeus, commonly called red raspberry, is, for the most part, an erect to spreading to sprawling, thicket-forming, deciduous shrub with biennial, often prickly, cane-like stems. It typically grows to 3-9’ tall. This species has two main varieties, R. idaeus var. idaeus (European raspberry) which is native to Eurasia and R. idaeus var. strigosa (American red raspberry) which is native to a large part of North America from Alaska and Canada south to California, Oklahoma and North Carolina. In the wild, raspberries typically grow in a variety of locations including open woods, ravines, heaths, stream banks, bluffs and wooded mountain slopes. Commercially grown raspberries are mostly cultivars of these varieties or crosses between the two.
Raspberry shrubs are primarily grown for harvesting the tasty fruits. Leaves are alternate, usually divided into 3-5 leaflets which are arranged pinnately, pedately, or less commonly palmately, but infrequently undivided. First year stems (primocanes) bear only leaves. Lateral branches in the second year (floricanes) produce leaves, flowers and fruits. Flowers are in clusters, racemes or panicles, but are occasionally solitary, and are generally white but sometimes pink to rosy-purple. Flowers bloom in spring. Each flower has five petals, five sepals, five bracts, numerous stamens, and several pistils clustered on a cone-shaped core known as a receptacle. Botanically the fruits are not berries (though they are usually called berries), but are coherent aggregations of tiny drupelets. Fruits separate from the receptacle when picked with each raspberry resembling a hollow cone. Fruits ripen in summer. Many wild raspberries have very little garden merit, and, if not properly cared for, can easily spread to form tangled masses of impenetrable, thorny stems.
Genus name is the Latin name for brambles (blackberry and raspberry).
Specific epithet means "of Mt. Ida" in reference to the belief that raspberries were first discovered on Mt. Ida in Greece.
'Prelude' is a vigorous, hardy, everbearing raspberry selection that features early fruiting (typically maturing in June) with a second, smaller crop in fall. Mature plants will reach up to 6' tall with a 5' spread. The firm, juicy, bright red, 0.75" wide berries are suitable for eating fresh, freezing, or making jams or jellies. The canes have an open growth habit and tend to have few thorns. This plant is protected by patent number PP11747.
Problems
Anthracnose, botrytis, root rot and other fungal diseases can cause serious problems that may necessitate chemical treatments. Cane borers and crown borers are potentially serious insect pests.
'Prelude' has good resistance to root rot.
Uses
Raspberries are primarily grown for harvest of their tasty fruits. Cultivars featuring raspberries superior in size and flavor to those of species plants are available in commerce for planting in home gardens plus are commercially grown for sale of the fruit around the world to those who covet the taste of a raspberry. The straight species is rarely grown in home gardens for fruit production.
Raspberries are sometimes grown for foliage accent in spreading colonies.