American Cranberry, Cranberry
Vaccinium macrocarpon

Family: Ericaceae

What it is like

Vaccinium macrocarpon is an evergreen Shrub growing to 0.2 m (0ft 8in) by 2 m (6ft) at a medium rate. See above for USDA hardiness. It is hardy to UK zone 2. It is in leaf all year, in flower from June to August, and the seeds ripen from August to October. The species is hermaphrodite (has both male and female organs) and is pollinated by Insects. The plant is self-fertile. Suitable for: light (sandy) and medium (loamy) soils, prefers well-drained soil and can grow in nutritionally poor soil. Suitable pH: mildly acid soils and can grow in very acid soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist or wet soil.

Height (m): 0.2

Where it is found

Acid boggy ground.

Eastern N. America. Occasionally naturalized in Britain.

Conservation Status:

Countries/locations it is found in

Asia, Australia, Britain, Canada, Europe, North America, Tasmania, USA,

How it is used

Food

Rating: 3

Fruit - raw or cooked. It can also be dried for winter use. Rich in vitamin C, the fruit is too acid for most peoples tastes to be eaten raw, so it is mainly used in pies, preserves etc. It is said that a teaspoon of salt added to the cooking fruit can take the place of half the sugar normally used. The fruit is between 1 and 2cm in diameter.

Medicine

Rating: 1

An infusion of the branches has been used as a treatment for pleurisy.

Antineoplastics: Inhibiting or preventing the growth or development of malignant cells. See also Antitumor, Cytotoxic and Cytostatic.

Appetizer: Improves the appetite

Hypoglycaemic: Reduces the levels of sugar in the blood.

Miscellany: Various medicinal actions that need more clarification.

Vitamin C: Plants good for their vitamin C content

Other

Rating: 4

Plants can be grown as a ground cover when planted about 1 metre apart each way. Plants spread rapidly when they are thriving.

Miscellany: A rag-bag of items that are difficult to categorise.

Food Forest: Plants for Edible Forest Gardens and Food Forests.

Ground cover: Ground Cover

How it is grown

Requires a moist or semi-boggy lime free soil, preferring one that is rich in peat or a light loamy soil with added leaf-mould. Prefers a very acid soil with a pH in the range of 4 to 4.5, plants soon become chlorotic when lime is present. Plants grow best in a poor soil, richer soils result in extra foliage production at the expense of fruit. Succeeds in full sun or light shade though it fruits better in a sunny position. Requires shelter from strong winds. A very dwarf shrub producing long slender creeping stems that root into the soil. Upright stems grow from the axillary buds in the second year and these upright stems flower and fruit the following year. Widely cultivated for its edible fruit in N. America, there are many named varieties. Cultivated plants are usually grown in artificial bogs that are often flooded in the winter. Plants can self-fertilize but cross-fertilization by insects results in higher yields. Cultivated plants take about 5 years to come into full bearing but will then crop well for 60 - 100 years. Dislikes root disturbance, plants are best grown in pots until being planted out in their permanent positions. Plants in this genus are notably resistant to honey fungus. For polyculture design as well as the above-ground architecture (form - tree, shrub etc. and size shown above) information on the habit and root pattern is also useful and given here if available. An evergreen. The root pattern is flat with shallow roots forming a plate near the soil surface. The root pattern is stoloniferous rooting from creeping stems above the ground.

Propagating it: Seed - sow late winter in a greenhouse in a lime-free potting mix and only just cover the seed. Stored seed might require a period of up to 3 months cold stratification. Another report says that it is best to sow the seed in a greenhouse as soon as it is ripe. Once they are about 5cm tall, prick the seedlings out into individual pots and grow them on in a lightly shaded position in the greenhouse for at least their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts. Cuttings in April of shoots 15cm long, in a sandy mix in a frame covered in plastic to keep them moist. Cuttings of half-ripe wood, 5 - 8cm with a heel, August in a frame. Slow and difficult. Layering in late summer or early autumn. Another report says that spring is the best time to layer. Takes 18 months. Division of suckers in spring or early autumn.

Best place to grow: Woodland Garden Sunny Edge; Dappled Shade; Ground Cover; Bog Garden;

Habit: Shrub

Hardiness: 0-0

Growth: Medium

Soil: Light (sandy), medium

Shade: Semi-shade, no shade

Moisture: Moist, wet

Things to keep in mind

Its other names

Local names

Large cranberry, Da guo yue jie, Airelle a gros fruits, Kranbeere, Mirtillo palustre, Arando trepador, Craisons,

Synonyms

Oxycoccus macrocarpus. (Ait.)Pursh.