Raspberry

Fruit of four species of raspberry. Clockwise from top left: Boulder raspberry, Korean raspberry, Australian native raspberry, West Indian raspberry

The raspberry is the edible fruit of a multitude of plant species in the genus Rubus of the rose family, most of which are in the subgenus Idaeobatus; the name also applies to these plants themselves. Raspberries are perennial with woody stems.

Major kinds of cultivated raspberries

Fruits of a golden or yellow raspberry cultivar

Raspberries are an important commercial fruit crop, widely grown in all temperate regions of the world.

Many of the most important modern commercial red raspberry cultivars derive from hybrids between R. idaeus and R. strigosus.^[1] Some botanists consider the Eurasian and American red raspberries all belong to a single, circumboreal species, Rubus idaeus, with the European plants then classified as either R. idaeus subsp. idaeus or R. idaeus var. idaeus, and the native North American red raspberries classified as either R. idaeus subsp. strigosus, or R. idaeus var. strigosus. Recent breeding has resulted in cultivars that are thornless and more strongly upright, not needing staking.

The black raspberry, Rubus occidentalis, is also occasionally cultivated in the United States, providing both fresh and frozen fruit, as well as jams, preserves, and other products, all with that species' distinctive, richer flavor.

Purple raspberries have been produced by horticultural hybridization of red and black raspberries, and have also been found in the wild in a few places (for example, in Vermont) where the American red and the black raspberries both grow naturally. The botanical name Rubus × neglectus applies to these naturally occurring plants, as well as horticulturally produced plants having the same parentage. Commercial production of purple-fruited raspberries is rare.

Blue raspberry, is a local name used in Prince Edward Country, Ontario, Canada^[2] for the cultivar 'Columbian', a hybrid (purple raspberry) of R. strigosus and R. occidentalis.^[3]

Both the red and the black raspberry species have albino-like pale-yellow natural or horticultural variants, resulting from presence of recessive genes that impede production of anthocyanin pigments.^{[citation needed]} Fruits from such plants are called golden raspberries or yellow raspberries; despite their similar appearance, they retain the distinctive flavour of their respective species (red or black). Most pale-fruited raspberries commercially sold in the eastern United States are derivatives of red raspberries. Yellow-fruited variants of the black raspberry are sometimes grown in home gardens.

Red raspberries have also been crossed with various species in other subgenera of the genus Rubus, resulting in a number of hybrids, the first of which was the loganberry. Later notable hybrids include boysenberry (a multi-generation hybrid), and tayberry. Hybridization between the familiar cultivated red raspberries and a few Asiatic species of Rubus has also been achieved.

Species

Until recently, the most commonly cultivated raspberries have been red-fruited hybrids between R. idaeus and R. strigosus.

Purple-fruited raspberry hybrids are becoming popular.

Examples of raspberry species in Rubus subgenus Idaeobatus include:

• Rubus crataegifolius (Korean raspberry)
• Rubus gunnianus (Tasmanian alpine raspberry)
• Rubus idaeus (European red raspberry)
• Rubus leucodermis (Whitebark or Western raspberry, Blue raspberry, Black raspberry)
• Rubus occidentalis (Black raspberry)
• Rubus parvifolius (Australian native raspberry)
• Rubus phoenicolasius (Wine raspberry or Wineberry)
• Rubus rosifolius (West Indian raspberry)
• Rubus strigosus (American red raspberry) (syn. R. idaeus var. strigosus)
• Rubus ellipticus (Yellow Himalayan Raspberry)

Several species of Rubus, also called raspberries, are classified in other subgenera, including:

• Rubus arcticus (Arctic raspberry, subgenus Cyclactis)
• Rubus deliciosus (Boulder raspberry, subgenus Anoplobatus)
• Rubus nivalis (Snow raspberry, subgenus Chamaebatus)
• Rubus odoratus (Flowering raspberry, subgenus Anoplobatus)
• Rubus sieboldii (Molucca raspberry, subgenus Malachobatus)

Uses

Fruit

Raspberries are grown for the fresh fruit market and for commercial processing into individually quick frozen (IQF) fruit, purée, juice, or as dried fruit used in a variety of grocery products. Traditionally, raspberries were a midsummer crop, but with new technology, cultivars, and transportation, they can now be obtained year-round. Raspberries need ample sun and water for optimal development. Raspberries thrive in well-drained soil with a pH between 6 and 7 with ample organic matter to assist in retaining water.^[4] While moisture is essential, wet and heavy soils or excess irrigation can bring on Phytophthora root rot, which is one of the most serious pest problems facing the red raspberry. As a cultivated plant in moist, temperate regions, it is easy to grow and has a tendency to spread unless pruned. Escaped raspberries frequently appear as garden weeds, spread by seeds found in bird droppings.

An individual raspberry weighs 3–5 g (0.11–0.18 oz),^[5] and is made up of around 100 drupelets,^[6] each of which consists of a juicy pulp and a single central seed. A raspberry bush can yield several hundred berries a year. Unlike blackberries and dewberries, a raspberry has a hollow core once it is removed from the receptacle.

Nutrients and phytochemicals

The aggregate fruit structure contributes to raspberry's nutritional value, as it increases the proportion of dietary fiber, which is among the highest known in whole foods, up to 20% fiber per total weight.^{[citation needed]} Raspberries are a rich source of vitamin C, with ~ 32 mg per serving of 1 cup (about 54% daily value), manganese (about 41% daily value) and dietary fiber (about 32% daily value). B vitamins 1–3, folic acid, magnesium, copper, and iron are present in raspberries.^[7]

Raspberries contain anthocyanin pigments, ellagic acid (from ellagotannins, see for instance the polyphenol ellagitannin), quercetin, gallic acid, cyanidins, pelargonidins, catechins, kaempferol and salicylic acid.^[8] Yellow raspberries and others with pale-colored fruits are lower in anthocyanins. Both yellow and red raspberries contain carotenoids, mostly lutein esters, but these are masked by anthocyans in the red fruits.^[9]

Animal research indicates antioxidant and antiproliferative (chemopreventive) effects may be associated with phenolics and flavonoids in various foods, including raspberries.^[10][11][12]

Raspberries are a low-glycemic index food, as are other berries.

Commercial production

Top producers of raspberries in tons Shown in 2011 order
Country	2010		2011
Russia	125,000	27%	140,000	26%
Poland	92,864	20%	117,995	22%
Serbia	83,870	18%	89,602	16%
United States	36,741	8%	48,948	9%
Ukraine	25,700	5%	28,100	5%
Mexico	14,343	3%	21,468	4%
United Kingdom	17,000	4%	16,761	3%
Canada	11,864	3%	12,285	2%
Azerbaijan	10,100	2%	11,000	2%
Spain	9,226	2%	9,559	2%
Total	471,322	100%	543,421	100%
Source: UN FAOSTAT [13]

Worldwide raspberry yield

Leaves

Raspberry leaves can be used fresh or dried in tisanes. They have an astringent flavor, and in herbal medicine are reputed to be effective in regulating menses.^{[citation needed]}

Cultivation

Cultivated raspberry, in flower in a garden

Various kinds of raspberries can be cultivated from hardiness zones 3 to 9.^[1] Raspberries are traditionally planted in the winter as dormant canes, although planting of tender, plug plants produced by tissue culture has become much more common. A specialized production system called "long cane production" involves growing canes for a year in a northern climate such as Scotland or Oregon or Washington, where the chilling requirement for proper bud break is attained, or attained earlier than the ultimate place of planting. These canes are then dug, roots and all, to be replanted in warmer climates such as Spain, where they quickly flower and produce a very early season crop. Plants are typically planted 2-6 per m in fertile, well drained soil; raspberries are usually planted in raised beds/ridges, if there is any question about root rot problems.

The flowers can be a major nectar source for honeybees and other pollinators.

Raspberries are very vigorous and can be locally invasive. They propagate using basal shoots (also known as suckers), extended underground shoots that develop roots and individual plants. They can sucker new canes some distance from the main plant. For this reason, raspberries spread well, and can take over gardens if left unchecked.

Raspberries are often propagated using cuttings, and will root readily in moist soil conditions. Using cuttings preserves the genotype of the parent, and is the preferred method of propagation when making large plantings.^{[citation needed]}

The fruit is harvested when it comes off the torus/receptacle easily and has turned a deep color (red, black, purple, or golden yellow, depending on the species and cultivar). This is when the fruits are ripest and sweetest. Excess fruit can be made into raspberry jam or frozen.

Selected important cultivars

Numerous raspberry cultivars have been selected.

Two types of raspberry are available for commercial and domestic cultivation; the summer-bearing type produces an abundance of fruit on second-year canes (floricanes) within a relatively short period in midsummer, and double or "everbearing" plants, which also bear some fruit on first-year canes (primocanes) in the late summer and fall, as well as the summer crop on second-year canes. Those marked (AGM) have gained the Royal Horticultural Society's Award of Garden Merit.

Red, early summer fruiting        

Red, midsummer

Red, late summer

Red, primocane, fall, autumn fruiting

Gold/Yellow, primocane, fall, autumn fruiting

Purple

Black

Diseases and pests

Raspberries are sometimes eaten by the larvae of some Lepidoptera species (butterflies and moths). Botrytis cinerea, or gray mould, is a common fungal infection of raspberries and other soft fruit. It is seen as a gray mould growing on the raspberries, and particularly affects fruit which are bruised, as it provides an easy entrance point for the spores.

Raspberry plants should not be planted where potatoes, tomatoes, peppers, eggplants, or bulbs have previously been grown, without prior fumigation of the soil. These crops are hosts for the disease Verticillium wilt, a fungus that can stay in the soil for many years and can infest the raspberry crop.^[21]

See also

• Chambord Liqueur Royale de France
• List of culinary fruits
• Raspberry ketone
• Red raspberry leaf, used as a herb

References

Further reading

• Funt, R.C. / Hall, H.K. (2012). Raspberries (Crop Production Science in Horticulture). CABI. ISBN 978-1-84593-791-1

External links

Wikimedia Commons has media related to Raspberry.

Look up raspberry in Wiktionary, the free dictionary.

Wikibooks Cookbook has a recipe/module on Raspberry

Wikisource has the text of the 1911 Encyclopædia Britannica article Raspberry.

• Raspberries & More (University of Illinois Extension)