Cloudberry

Contributor: Kåre Rapp

Common Names
Scientific Names
Uses
Origin
Crop Status
Botany
1. Taxonomy
2. Morphology
Crop Culture
1. Wild Crops
2. Cultivated Crops
Germplasm
1. Collection
2. Commercial Plant Source
Key References
Selected Expert

Common Names

English: cloudberry
German: Moltebeere, Torfbeere
Canada, USA (Alaska): cloudberry, bakeapple

Scientific Names

Species: Rubus chamaemorus L.
Family: Rosaceae

Image by Kåre Rapp

Cloudberry may be eaten as fresh fruit, or following freezing and defrosting, added sugar and cream or whipped cream. They are used as dessert, in jam, juice consentrate, and as a layer in cakes (cream cakes). Liqueur may also be produced from cloudberries.

Formerly, this fruit was an important remedy for scurvy among hunters in the Arctic. Due to the high content of benzoic acid, a natural conservation chemical, the berry is easy to store in its fresh state in a refrigerator or a cold room.

Origin

Cloudberry is native to most of the northern circumpolar areas. It is found in Scandinavia, Siberia/Russia, Canada and the USA (Alaska and New Hampshire). It has also been observed in Greenland and Spitzbergen.

Crop Status

Cloudberry is a herbaceous, perennial plant species. Often called a "pioneer plant" on account of its rapid regrowth, prior to other species, following soil disturbance on native peat land. For example along verges following road construction during peat land with cloudberry plants, and also after agricultural activity on peat land where cloudberry is growing.

Berries on the market today are hand-picked on native cloud-berry peat land. Both European and World market demand are largely unmet for this very special small-fruit.

Cultivation methods for cloudberry have been developed and introduced to farmers and other landowners in Norway. Machinery has also been developed for combined drainage and soil cultivation of peat land.

Two female and two male varieties of cloudberry have been developed for northern Norway, after selection and breeding at the Holt Research Centre, Tromsø. The varieties are registered according to the international UPOV rules.

A system for vegetative propagation has been developed to manage the registered varieties. Varieties suitable to southern districts of Norway are expected to be available on the market within a few years.

Botany

Taxonomy

Cloudberry (R. chamaemorus L.) is an octoploid species (2n = 56). This is the only species in group 3, Chamaemorus, under the genus Rubus. Cloudberry has been crossed with raspberry (R. idaeus L., 2n = 14) both spontanousely and artificially, and crossed artificially with the bramble R. fruticosus L. (2n = 28). However, all crossing offspring have been sterile. [Raspberry is in group 1 (Idaeobatus) and the bramble is in group 4 (Eubatus) under the genus Rubus.]

Morphology

Cloudberry is a dioecious, herbaceous, perennial plant species. It has a primary vegetative propagation, developed from juvenile buds on the rhizomes which grow about 10 cm below the soil surface.

The fruit is a berry composed of several small nut-fruits (drupelets) each bearing a nut-seed. These small nut-seeds are a special characteristic of desserts comprising berries and cream.

Crop Culture

Wild Crops

Almost all of the cloudberries on the market today come from production on native (non-cultivated) cloudberry peat land. This wild crop is primarily produced on native sphagnum peat bogs, frequently surrounded by forest providing a natural shelter.

The most favourable growing conditions are obtained on peat bogs between 0.5 and 1 meter in depth, with pH-values between 3.5 and 4.5, and with the ground water 40 to 50 cm below the surface. The berry yield level on native peat-land is 20 to 50 kg/ha (8 to 20 kg/acre).

Cultivated Crops

Cultivation methods for commercial cloudberry production have recently been developed by the Holt Research Centre, Tromsø.

Three cultivation methods (I, II, and III) are briefly described below, and are advised for cultivation practice.

Method I. Deep-fertilization with NPK fertilizer.

Artificial mineral fertilizers are put into holes, some 15 to 20 cm in depth made with wooden poles. This method is advised only if there are sufficient of natural female plants, and if there is no need for drainage. The use of this selective fertilization method is due to the fact that the cloudberry plant has most of its roots on the 15 to 20 cm horizon in the mires, whereas most of the competing species are more shallow rooted while some are deeper rooted.

Method II. Soil cultivation combined with deep-fertilization.

In this method strips are plowed or milled up as beds on the sphagnum mires. Again, this method is advised only if there are sufficient of natural female plants. These plants will soon break through the peat bed as a pioneer, providing the basis for a virgin community of young cloudberry plants. The furrows plowed and/or the ditches milled up will provide also drainage.

Method III. Full cultivation.

In this method soil cultivation is combined with plant propagation and planting, and deep-fertilization. This method is recommended if there are too few female plants in the native stand to provide the basis for a community following soil cultivation. For this method, the varieties will have to be propagated and planted at a density of 30,000 to 40,000/ha (12,000 to 16,000/acre) in order to provide an optimal cultivated stand.

Rapp, K. and K. Steenberg. 1977. Studies of phosphorus uptake from different depths in cloudberry mires using P32-labelled fertilizer. Acta Agric. Scand. XXVII:319-325.
Rapp, K. and C. Stushnoff. 1979. Artificial freezing of Rubus chamaemorus L. for estimation of genetic components of cold hardiness. Meld. Norg. Landbr.Høgsk. 58(15):1-14.
Rapp, K. 1987. About the sex ratio and sex differentiation in cloudberry (Rubus chamaemorus L.). Jord og Myr 11:1-11.
Rapp, K. 1988. Number of pistils, an alternative criterion when selecting for high productivity in Rubus. Norwegian J. Agr. Sci. 2:1-4.
Rapp, K. 1991. Selection for high berry yield, and development of varieties of cloudberry (Rubus chamaemorus L.). Norsk Landbruksforsking 5:359-367.
Rapp, K. 1992. Cultivation and plant breeding of wild berries, particularly cloudberry, for northern regions of Norway. Proc. 1st Circumpolar Agr. Conf., Yukon, Canada, September 1992. p. 171-172.

Selected Expert

Kåre Rapp, The Norwegian Crop Research Institute, Holt Research Centre, PO Box 2502, N-9002 Tromsø, Norway.
Phone: 47 77684875 Fax: 47 77680173
E-mail: evawm@holt.no

Contributor: Kåre Rapp

Last update Tuesday, February 24, 1998 by aw