Fruit and Vegetables

Raspberry - Rubus idaeus


GeneralitŠ°


Perennial sarmentose shrub native to central-northern Europe; It consists of a small-sized stump, from which grow long vines with a two-year development, covered with a thin down, sometimes thorny, arched and flexible, growing up to 150-200 cm in height. In spring it produces small pinkish white flowers, gathered in pyramidal inflorescences; some varieties produce fruit in the summer, on the branches of a year; other varieties produce fruit in the spring on the branches of a year and in summer on the new shoots. The fruits of the raspberry are sweet and juicy, they are small drupes attached to each other, around the receptacle, from which they come off easily; in autumn the branches that have fructified during the previous summer are pruned. Raspberries are used to prepare jams and liqueurs, the leaves are also used in herbal medicine.

The raspberry


It belongs to the same family as apple and pear and includes several species that are widespread practically all over the world. We are talking about raspberry, a bushy species to which we dedicate a detailed cultivation form. The plant, which appears spontaneously in some wooded areas, also lends itself to being cultivated both in the garden and on a large scale. The techniques and methods of cultivation vary according to the variety chosen.

Exposure



Place in a sunny or partially shady place; they prefer fresh places, possibly with the lower part of the plant far from the direct rays of the sun. Raspberries do not fear the cold and tend to develop widely over the years.

Raspberry morphology


Raspberry belongs to the boundless family of the Rosaceae and to the genus Rubus. It includes several species, but the most known and cultivated is mainly the European one, namely the Rubus idaeus L, commonly known as European raspberry. The plant, native to Europe and Asia Minor, has a bushy growth habit and also includes other varieties that are mainly distributed overseas and little cultivated in Europe. Thanks to crosses between the different varieties of raspberry, however, cultivars have been obtained that resist any climatic and soil condition and the most common pests and diseases. The plant is presented with about three, five deciduous, oval, dark green leaves, consisting of a serrated edge and with fruits that depending on the variety can take on a color ranging from red, purple and black. The vegetative cycle of raspberry is two-year and continuous. The European raspberry, in particular, is a bushy plant composed of numerous biennial buds that expand and renew themselves continuously. The roots of the plant are instead superficial and perennial, formed by squat and rhizomatous main roots, and by collated secondary roots. The buds of the year are called suckers, while the shoots of two years are called "fruiting shoots". These vegetative parts, light green in color, can sometimes be covered with small spines and can even reach a length of two meters. If they grow from buds placed along the roots, they are also called root suckers, if they appear at the base of the branches and at the collar, they are called "collar suckers".

Watering


Generally they are satisfied with the rains, even if it is advisable to water them in the summer period, before the harvest of the fruits, to avoid that they dry out too much, above all in case of prolonged periods of drought.

Ground



Raspberries love soft soils, rich in organic matter and very well drained. They settle in autumn after having enriched the soil with mature manure; after implantation, the stems are cut about 20-30 cm above the ground. In autumn, organic or slow-release fertilizer is supplied; every 8-10 years it is advisable to move the lamp stumps, to always get a good fruiting.

Multiplication


It usually occurs by dividing the clumps, in fact the young basal suckers root easily once separated from the mother plant.

Pests and diseases


Generally raspberries do not get sick easily, even if the fruits attract numerous insects and animals that feed on them.

Flowers and fruits



The raspberry flowers, white in color, are gathered in small racemose inflorescences. The development of the same occurs in mid-May with the appearance of apical flowers and then of axillary ones which open at the basal leaves. Generally, the raspberry bloom lasts for about a month, then until mid-June. The fruits, instead, called "sorosi", are composed of a set of drupes that joined together form the well-known blackberry, also called "fruit of the forest". The shape of the blackberry can be round or elongated and conical, while the color varies from pale pink, to ruby, to intense red and almost purple.

Raspberry variety



There are many varieties of raspberry and it would be impossible to list them all. Among the most famous we remember the rubus strigosus, or wild raspberry, from the United States, with smaller, darker shoots and red fruits similar to the European raspberry. It seems that there is no difference between the two species and both are included in the common name "red raspberry". In addition to the red raspberry there is also the black raspberry, with purplish-colored fruits so intense that they seem black. The botanical name of this second variety, always originating from the United States, is Rubus occidentalis. The purplish raspberry, botanically known as Rubus neglectus, is always American. The different varieties of raspberry are also classified according to the age and the type of fruiting. In this sense, there are the unifying raspberries, which bear fruit only once a year, and the re-flowering or biferous raspberry, which bears fruit twice a year. The cycle of these plants is always biennial, but in the standard varieties, during the first year the formation of the suckers takes place and in the second, that of the fruits; in bifera varieties, on the other hand, suckers and fruits appear simultaneously both in the first and in the second year.

Habitat and raspberry cultivation



The rubus idaeus It is a plant that grows wild in mountain areas, mainly in the undergrowth and at altitudes not exceeding two thousand meters above sea level. The ideal habitat of the rubus idaeus it is therefore represented by a woody environment, moist, fresh and rich in organic substance. Thanks to cultivation for productive and ornamental purposes, raspberry is now grown all over the world. It is currently particularly common in the United States, Canada and Chile. In Europe, raspberry cultivation is widespread in Poland, the United Kingdom, Spain, Austria, Holland, Germany, Switzerland and Italy. In our country, the plant is cultivated both in the southern and northern regions. Raspberry cultivation can take place outdoors and in pots. The plant's modalities change according to the cultivated species. The standard varieties are cultivated with a traditional espalier, that is with branches all placed in the same row, or espalier in alternate years, with separate rows and dedicated to the production of the renewal shoots and to the production of the fruiting shoots. These rows can be reversed from the second year. Bifera varieties are instead cultivated with a traditional espalier.

Land and repotting



Raspberry prefers fresh, well-drained, humus-rich soils with a slightly acid pH and do not exceed 6.5. The plant does not tolerate clayey, hard, compact and too moist soils. In fact, these soils can cause asphyxia of the roots and fungal diseases that can bring the entire plant to death. Even the limestone-rich soils are to be avoided, because, in the most sensitive varieties, they can give rise to chlorosis, or to the yellowing of the leaves caused by the lack of absorption of iron by the roots. The raspberry grown in pots should be planted in a new container every eight or ten years, so as to always guarantee a good fruiting of the plant.

Temperature and exposure


Raspberry fears high temperatures but also intense and prolonged cold. The ideal exposure for the plant is in a partially shaded place where it can receive sunlight during the coolest hours of the day. Instead, avoid hot and dry places. Raspberry roots can also be damaged by the cold wind. This climatic condition often leads to the burning of the roots or their damage. The same roots can burn due to sudden drops in spring temperatures. Changes in temperature can also damage the shoots that develop from the soil. For this reason, the soils of the areas at the bottom of the valley are to be avoided, where cold air accumulations are more likely.

Multiplication and planting



The raspberry reproduces by pollination, or through the intervention of bees, or by division of the suckers taken from the mother plant. The planting of the plant, as already said, can take place in the open field and in pots. The seedlings with already rooted suckers should be planted during the vegetative rest, or in autumn. In regions with particularly harsh climates, however, it is advisable to plant them in spring and in a cool, damp place. Instead, the potted seedlings are planted by the middle of May, placing the containers in a place sheltered from the wind and drafts. The raspberry planting operations are quite simple because they only include the insertion of the ground bread inside the holes.

Irrigation


The raspberry should be irrigated immediately after planting, at the vegetative growth, during flowering and during fruit growth. In these phases and especially during the growth of the fruits, the irrigations must be abundant. After harvesting, and especially in autumn, irrigations should instead be progressively reduced, so as to favor the maturation of the stem and the development of new roots. The quantities of water to be distributed vary according to the climate and the type of soil. In shallow soils, frequent irrigation with little water will be necessary, while in medium soils greater quantities of water will have to be distributed but spaced between one application and another. Water can be distributed via sprinkler irrigators that water the foliage, or via the dripper system. In light soils and in cool and ventilated climates it is advisable to irrigate with the sprinkling system. Always avoid excess water and water stagnation, which can cause fungal diseases and fruit rot.

Fertilizer


Raspberry is a plant that during its development bears a considerable waste of energy. The greatest effort of the plant occurs during the development of the shoots and the fruits. Therefore, the fertilization foresees different interventions, both during planting and production and harvesting. Before planting, a bottom fertilization of the soil must be carried out, which must be enriched with bovine manure or, in the absence of it, with mineral fertilizers. The latter are also administered during the phases of growth and production and over a period of time that goes from the vegetative restart to the beginning of the harvest, in the standard varieties, and half harvested for the re-flowering varieties. Every two years the soil must also be enriched with mature and decomposed manure. Care must be taken that the same manure is easily absorbed by the soil so as not to constitute an obstacle to the escape of the basal suckers. If you do not want to make too many fractional mineral fertilizers, you can choose a slow release fertilizer for fruit plants, to be administered every three or four months.

Pruning



Raspberry needs little pruning which is quite simple to do. In general, we proceed by eliminating the branches that produced the fruit to make room for new unproductive shoots. The latter will be subsequently cut and trimmed in the apical part. The operations described above are carried out every year, but in different periods which vary according to the species cultivated and the farming system chosen. In the traditionally produced standard varieties, pruning is carried out after harvesting the fruit, cutting the productive shoots at the base. Thinning and topping are performed instead in autumn. A second intervention on the production shoots is carried out in spring. In regular varieties in alternate years, the productive shoots are eliminated in autumn only when they are completely dry. The re-flowering varieties can be pruned in autumn by eliminating the apical branches or by cutting the basal ones completely flat. To avoid the development of pests and diseases, it is advisable to burn and promptly remove all pruning residues.

Raspberry - Rubus idaeus: Pests and diseases



Raspberry can be affected by insect pests and diseases. The most frequent insects in the raspberry are aphids, mites, beetles and curculoid beetles. The latter, in the larval stage, are similar to worms that damage the fruits making them non-marketable. Mushrooms, viruses and bacteria can cause very serious diseases in the raspberry such as root cancer, white hatred and gray mold. Among the virus diseases we remember the mosaic of leaves and the curl of the leaves. Many adversities of raspberry can be prevented by setting correct cultivation methods, choosing resistant cultivars and selecting the right soil.