Plant, care and harvest cranberries

Cranberries are found all over the northern hemisphere and have long been used as food. We introduce the different types of cranberries and give tips on cultivation and use.

The tart and sour fruits of the cranberries were already used by the Nordic natives as a vitamin-rich food. The cranberry, which is in great demand as a vitamin C supplier, is also one of the cranberries. In this article you will find information about the origin and different types of cranberries, as well as the successful cultivation and use of the cranberry fruits.

Cranberry: flowering, characteristics and origin

The species group of cranberries is closely related to the blueberries (Vaccinium myrtillus and Vaccinium corymbosum) and Cranberries (Vaccinium vitis–idaea) related. All three types of berries belong to the same genus (Vaccinium) and to the heather family (Ericaceae). The cranberries occur as cold and frost tolerant bog dwellers in all subpolar to moderate climatic zones of the northern hemisphere around the Arctic Circle. Cranberries are ground cover, they grow low and creeping. The leaves are elongated and lanceolate, they are hardly larger than 1.5 centimeters and shiny dark green. The flowering of the cranberries is typical of the heather family: small and with rolled back petals, white to pink or reddish. They bloom between May and July. Bees and bumblebees like to pollinate the flowers. Round berry fruits later form from it, which by the time the cranberries are harvested - between the end of August and October - turn red to dark red, sometimes shiny. The taste of cranberries is generally tart and tart. The fruits have a very long shelf life and are mainly enjoyed processed.

The different types of cranberries

There are various species of cranberries that have developed in their respective homeland. They differ in growth and fruit texture. We introduce you to the four types of cranberries.

Common cranberry (Vaccinium oxycoccos)

The common cranberry or bogberry is widespread in boggy, acidic locations in Great Britain, Scandinavia and northern Russia. However, it can potentially also find a suitable habitat in moor areas in many European countries, including Germany. The widely creeping subshrub has leaves a maximum of 1 cm long, which shine dark green in summer and turn reddish in winter. From June to July the common cranberry blooms on long hairy flower stalks and then forms pea-sized, dark red fruits when ripe. These taste juicy and sour, have a high vitamin C content and are used like cranberries. Ordinary cranberries are therefore not only suitable as an ornamental but also as a very high-yielding crop.

Large-fruited cranberries (Vaccinium macrocarpon)

The large-fruited cranberry is also known as the cranberry or American cranberry. It originally comes from the boggy and coastal areas of Northeast America and Canada, but also grows well in this country. Commercial cultivation has long been important in the states of Oregon and Washington. The ground-covering cranberry bush grows to a height of 10 to 30 cm and forms long, creeping, evergreen shoots. The white-pink flowers, rolled up towards the back, appear from June to July, the dark red, 1 to 2 cm large, round cranberry fruit ripens from the end of September. In rough locations, cranberries are sensitive to frost and drought, so they need a somewhat protected location. Because of their size and the many varieties available, cranberries are well suited to growing, and they are a little less specific in terms of their location requirements.

Small fruity cranberries (Vaccinium microcarpum)

The small-fruited cranberry is widespread in large parts of Northern Europe, including Germany, also in North America and slightly in Northern Asia. In contrast to the common cranberry, it produces smaller fruits and leaves as well as shorter shoots. The dwarf shrub is only 5 cm high and develops around 30 cm long, evergreen shoots. The blooming period of the tiny bell-shaped flowers extends from May to July. Later on, the juicy, sour fruits of the small-fruited cranberries sit on long, hairless stems, and take on a dark red color when ripe in late autumn. After exposure to frost, the berries acquire a sweeter taste. The small-fruited cranberries are more of an ornament than a useful plant, because they grow slowly and only make small berries.

Southern cranberry (Vaccinium erythrocarpum)

The southern cranberry (Vaccinium erythrocarpum subsp. erythrocarpum) or "Southern Mountain Cranberry" occurs in the mountainous southeastern United States. As an Asian subspecies (Vaccinium erythrocarpum subsp. japonicum) however, it is also native to Korea, China, and Japan. The deciduous shrub reaches heights of 1.5 meters. The reddish flowers with rolled back petals that appear in June are particularly striking. In autumn, translucent, sometimes dark red berries with a sour, tart taste develop from it. The southern cranberry is easy to harvest because the comparatively large shrub has a worthwhile amount of berries.

Planting cranberries: location and procedure

As bog dwellers, the common cranberries and the small-fruited cranberries are tied to quite special locations. All representatives of this genus need moist, acidic and sandy-humic, but not particularly nutrient-rich locations that never dry out completely. Calcareous, sandy, clayey or too dry soils are completely unsuitable for cranberries, they perish there in a very short time. In these gardens the bog dwellers can only be cultivated in pots and tubs. Cranberries and the southern cranberries are a little less demanding and can usually be planted in bog beds. For this purpose, the uppermost layer of soil is removed and replaced over a large area at a height of 15 to 20 cm. The pH value of the soil is lowered to 4 to 5 so that the bog dwellers feel comfortable. You can use the removed topsoil for balcony boxes, pots or raised beds. To create good site conditions for cranberries, mix rhododendron soil with approx. 10% sand and sour materials such as bark humus, spruce needles or grape marc. With this mixture you can now replace the excavated topsoil, roll the whole thing on or let it sink for two weeks.

After the soil has been prepared, the cranberries are planted. In the case of young plants, 7 to 9 plants are placed on a square meter, and this soon results in a dense cranberry meadow. The plants are not set lower than they were in the potty. Water well after planting so that sufficient soil is flushed to the roots and the cranberries can take root. Then cover the surface of the earth between the plants with fine bark mulch. This protects the slow-growing cranberries from heavy weed growth and keeps moisture in the soil.

The most important maintenance measures

Cranberries require minimal maintenance. The effort is mainly limited to removing weeds in the bed. In dry summers, cranberries should be watered regularly.
The nutrient requirement of cranberries is very low, but fertilization may be necessary on mulched areas because the breakdown of bark mulch and the like binds nitrogen by microorganisms. If you are seeing slow growth and little new shoots, then using an organic liquid fertilizer like ours is advisable Plantura organic flower & balcony fertilizer, recommended. Use the fertilizer only in small doses, because cranberries can form atypical, long shoots or fewer flowers due to excessive nutrient content.
Cranberries don't need to be cut. Only sick or aged shoots or overgrown plantings should be pruned gently.

The leaves and flowers of cranberries can be damaged by late frosts in May; after budding, temperatures must not drop below -2 ° C. It is better to cover cranberry plants with fleece or jute at the time of the ice saints.

Propagate cranberries

If you want to propagate your cranberries, you can do this by cuttings from the young shoots. To do this, cut off annual shoots about five centimeters long and put them almost entirely in a prepared soil mixture of acidic potting soil and sand. In the following weeks, the cuttings should always be kept moist until they have formed roots and can be planted out.
Shoots lying on the ground can be used for subsidence: They also quickly form roots at the contact point with the ground. These rooted shoots are cut off and moved directly to a suitable location.

Are cranberries poisonous?

Cranberries are not poisonous and are also difficult to compare with slightly poisonous relatives, such as bogberries (Vaccinium uliginosum), to be confused. The latter forms berries with dark blue frosting on bushes up to 0.8 meters high, which lead to intoxicating states and dizziness after consuming larger quantities. All types of cranberries can be eaten raw, even if they are often too sour.

Cranberries: Harvest Time and Use

The harvest time for the various types of cranberries extends from the end of August to October. They are usually picked individually by hand. With the help of a harvesting comb, such as that used in commercial cranberry cultivation, the small berries can be stripped and picked up much more easily and quickly. The berries remain in nature during winter and can still be consumed the following spring. The fruits of cranberries can be kept cool for several months. This is due to the abundant preservative ingredients such as vitamin C, benzoic acid and vaccinine, but also to the protective wax layer around the berries.

In addition to being eaten raw, the red fruits are processed into healthy cranberry juice, jam and compote. Similar to lingonberries, they are served with game dishes. Incidentally, cranberries do not need any additional gelling agent when they are preserved, as their high pectin content allows them to thicken by themselves. In Finland and Russia, common cranberries are used to make an alcoholic drink called kvass. Cakes and pastries can also be refined with the fresh, sour fruits. Dried cranberries keep for a long time and enrich mueslis, for example, with their high vitamin C content and refreshing acidity.

Not only cranberries can be found in our forests, they too blackberry (Rubus fruticosus) is at home there. We reveal what is important when choosing and planting berry fruit.