American cranberry

American cranberry: how do you recognise it?

Habit

Creeping, evergreen dwarf shrub of 10–20 cm, with long creeping stems.

Leaf

Alternate, elliptic, 0.5–1.5 cm, leathery, glossy green with a slightly rolled edge; reddish-brown in winter.

Stems

Thin and trailing, up to 1–2 m long, rooting at the nodes, with short, upright side shoots.

Flower

Pink flowers (1 cm) with 4 swept-back petals and a beak of stamens, June–July.

Fruit

Glossy red, sour berries (1–2 cm), September–October.

Difference from cranberry (Vaccinium oxycoccos)

Cranberry has even finer stems, smaller, pointed leaves that are white underneath, and smaller berries; it grows wild in raised bogs.

Difference from cowberry

Cowberry forms upright little bushes with gland dots under the leaves, white bells and berries in clusters.

Flowering: June–July · Harvest and fruit: September–October · Pruning: March–April

Looks like it, but isn’t

• Cranberry (Vaccinium oxycoccos): even finer stems, smaller, pointed leaves that are white underneath, and smaller berries; wild in raised bogs.
• Cowberry Vaccinium vitis-idaea: upright little bushes with gland dots under the leaves, white bells and berries in clusters. Difference from cowberry

Why grow it?

• Your own cranberries in September–October, for sauce, juice or baking.
• Evergreen ground cover that turns reddish-brown in winter.
• Pink flowers in June–July for bees and bumblebees.
• Suits a wet, acid spot or a container on the patio.

American cranberry: where does it grow best?

• Full sun: in shade it flowers and fruits poorly.
• Acid, humus-rich soil (pH 4–5.5) that always stays moist; not on chalk or clay.
• If you don’t have acid soil, grow it in a container or wide pot of ericaceous compost.
• One plant covers about 1 m² after a few years.

Light

Full sun

Legal basis

Acid soil

Moisture

Moist to wet

Size

0.2 m tall, 1 m wide

Hardiness

Throughout Belgium, no protection needed

Goes well with

• Highbush blueberry: Likes the same acid, moist soil; the cranberry creeps around the bushes as ground cover.
• Cowberry: An evergreen berry shrublet for the same acid soil.
• Cross-leaved heath: Flowers in summer on wet, acid soil, just like the cranberry.
• Bog-myrtle: A native shrub of wet, acid soil, with fragrant leaves.

Good and bad companions

Goes well with

• Likes the acid soil near: scots pine, black pine, weymouth pine, english oak, sessile oak, giant redwood
• Like acid soil, just like this plant: heather, rhododendron, japanese skimmia, raspberry, highbush blueberry, witch hazel, broom, gorse

Best kept away from

• Do not plant under the dense crown of these trees: norway spruce, european silver fir, nordmann fir, douglas fir, yew, horse chestnut, norway maple, sycamore

American cranberry: when and how to plant it?

1. Plant from a pot in spring (March–May) or in September–October.
2. Fill the bed or container with ericaceous compost mixed with some sand.
3. Space the plants 30–50 cm apart for a mat that closes quickly.
4. Water in with rainwater and keep the soil well moist for the first few months.

Care

Watering

Keep the soil moist at all times, with rainwater: tap water is often limy.

Feeding

Little needed; in spring a little fertiliser for ericaceous plants.

Weeding

Pull out grasses and weeds from the mat: the low stems are quickly smothered.

Sanding

A thin layer of sand every few years, in spring, makes the stems root again and gives more upright shoots.

Harvest

Pick in September–October when the berries are deep red; in the fridge they keep for weeks.

Tip: No acid soil? Plant it in a wide container of ericaceous compost and water only with rainwater: you can harvest cranberries even on a patio.

American cranberry: when to prune it?

Pruning months: March–April.

When: In March–April.

How:

• Little needed: trim overlong, bare runners so that more upright, fruiting shoots develop.
• Thin out crowded patches and cut away dead stems.

Caution: Needs acid, moist soil (pH 4–5.5): water with rainwater rather than tap water.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Natural layers

The stems root by themselves at the nodes: in spring, cut off a rooted piece and plant it elsewhere.

Cuttings

In spring, push 10–15 cm pieces of stem into moist, acid cutting compost; they root easily.

American cranberry: how does it get through the winter?

Hardy throughout Belgium: no protection needed.

• Fully hardy; the leaves turn reddish-brown in winter.
• In a pot: put it in a sheltered spot and don’t let the compost dry out, not even in winter.

Diseases and pests

• Yellow leaves: The soil isn’t acid enough, or you are using limy tap water. Use rainwater and an ericaceous fertiliser.
• Drying out: Brown, shrivelled stems after a dry spell, especially in a pot. Water regularly with rainwater.
• Weeds: Grasses grow through the low mat and smother it. Weed regularly, especially in the first few years.
• Few berries: Too much shade, or too many long runners. Give it full sun and trim the runners.

Through the year

• March: Pruning: trim overlong runners.
• April: Last pruning; planting; a little ericaceous fertiliser and perhaps a thin layer of sand.
• May: Weed, and water with rainwater in dry spells.
• June: Flowering begins.
• July: Flowering for bees and bumblebees; keep the soil moist.
• September: Harvest begins.
• October: Finish the harvest; planting is still possible.
• November: The leaves turn reddish-brown for winter.

What can you use it for?

Food and drink

Sour berries for sauce (with turkey and game), juice, drying or baking; harvest in September–October.

Garden and landscape

Evergreen ground cover for a wet, acid spot, or in a container of ericaceous compost.

Edible and useful

Berries (September–October)

Pick the berries from mid-September to the end of October, as soon as they are an even, deep red. They turn white first and then red: wait until there are no white patches left. The berries hang on thin stalks and may stay on the plant until after the first light frosts. Pick by hand or comb them carefully from the runners, and leave any berries that are soft or mouldy. Raw, they are very sour: do not taste too many before cooking.

Storing

First sort out any soft or mouldy berries. Fresh berries keep for 1–2 months in an open container in the fridge. They can be frozen without any preparation and go into the pan straight from frozen. Keep dried berries in a closed jar; sauce and syrup go in the fridge.

Caution: Only eat fully ripe, red berries of the large cranberry (Vaccinium macrocarpon) from your own garden. Raw they are very sour but not poisonous; cooked they taste best. Do not confuse them with the red berries of poisonous ornamental plants such as cotoneaster (Cotoneaster), skimmia or firethorn: the cranberry is a creeping, evergreen dwarf shrub with small, leathery leaves and berries hanging on thin stalks. Do not pick wild cranberries (Vaccinium oxycoccos) in bogs and nature reserves: they are rare and fragile, and in reserves everything stays where it is. Throw away mouldy berries, do not pick from sprayed plants and never eat anything you have not identified with certainty.

Eating and using is at your own risk: see the terms of use.

Recipes

• Cranberry sauce (Compote · ± 400 ml · 20 min)
• Dried cranberries (Dried · ± 150 g · 1 hr + 10–14 hrs drying)
• Cranberry and orange loaf cake (Dish · 1 loaf tin of 25 cm (± 10 slices) · 20 min + 55 min baking)
• Cranberry syrup (Syrup · ± 400 ml · 30 min + 30 min draining)

Did you know?

• The flower looks like the head of a crane: ‘crane-berry’ became cranberry. On farms the fields are flooded at harvest time, so the berries float to the surface.
• On the Dutch island of Terschelling, American cranberry has grown wild in the damp dune slacks since the mid-19th century; according to the story, a barrel of cranberries washed ashore there.
• Ripe berries contain small air pockets: they float and bounce. Growers use this to test their quality.