Bog bilberry

Bog bilberry: how do you recognise it?

Habit

Branched, deciduous dwarf shrub of 20–60 cm.

Leaf

Alternate, obovate, 1–3 cm, untoothed, bluish-green with clearly visible net veins; deciduous.

Twigs

Round, brown twigs (neither green nor angled).

Flower

White to pink, urn-shaped bells (5 mm), 1–4 together, May–June.

Fruit

Blue berries with a waxy bloom (6–10 mm) and white flesh, July–September; edible but bland.

Difference from bilberry

Bilberry has green, angled twigs, toothed pale green leaves and berries with purple flesh.

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

Identify by feature: Blue berries

Looks like it, but isn’t

• Bilberry Vaccinium myrtillus: green, angled twigs, toothed pale green leaves and berries with purple flesh. Difference from bilberry

Why grow it?

• A very rare, native plant of raised bogs: a piece of real nature in a wet heather garden.
• White to pink bells in May–June for bumblebees.
• Bluish-green leaves that turn red in autumn.
• Stays low and hardly needs pruning.

Bog bilberry: where does it grow best?

• Full sun; in shade it grows and flowers poorly.
• Acid, nutrient-poor soil that stays permanently moist to wet, such as peaty sand.
• It cannot tolerate lime: no chalky soil and no limy tap water.
• Allow about 60 cm width per plant.

Light

Full sun

Legal basis

Acid soil

Moisture

Moist to wet

Size

0.5 m tall, 0.6 m wide

Hardiness

Throughout Belgium, no protection needed

Goes well with

• Cross-leaved heath: Grows naturally on the same wet, acid heath, with pink bells in summer.
• Bog-myrtle: A fragrant, native shrub of wet, acid heaths and bogs.
• Creeping willow: A low, native willow that also grows on wet heath, with early catkins for bees.
• Cranberry: A tiny creeping shrub of raised bogs with red berries, for the wettest spot.

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

Bog bilberry: when and how to plant it?

1. Plant pot-grown plants from a nursery that grows native plants in spring or in September–October; never take plants from the wild.
2. On ordinary garden soil, create a wet, acid spot with sand, acid leaf mould and needle litter. Don’t use peat: digging peat destroys the very places where bog bilberry grows.
3. Plant at the same depth as in the pot, about 40–50 cm apart.
4. Water generously with rainwater after planting and keep the soil moist at all times.

Care

Watering

Keep the soil permanently moist with rainwater; it does not tolerate drying out.

Feeding

Don’t: bog bilberry grows on nutrient-poor soil, and fertiliser only helps grasses and weeds.

Weeding

Pull out grasses and tree seedlings such as birch in good time.

Mulching

A thin layer of needle litter keeps the soil acid and moist.

Tip: Make a small bog garden: dig a hole 30–40 cm deep, line it with pond liner pierced with a few holes at the bottom, fill it with sand and acid leaf mould, and water with rainwater. Bog bilberry, cross-leaved heath and cranberry grow well there together.

Bog bilberry: when to prune it?

Pruning months: March–April.

When: In March–April, if needed.

How:

• No pruning needed; in a garden, at most remove dead or overlong twigs.
• On wet heath, grazing or mowing keeps the vegetation open.

Caution: Don’t cut back all the twigs: the flowers, and so the berries, come on last year’s twigs.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Cuttings

In summer, take 5–8 cm cuttings from young shoots and root them in a moist mix of sand and ericaceous compost, under plastic.

Layering

Peg a low twig to the ground and cover it with acid soil; after a year you can cut it free.

Bog bilberry: how does it get through the winter?

Hardy throughout Belgium: no protection needed.

• Fully hardy: it grows far into the far north.
• Bare in winter; leave the fallen leaves as mulch.

Diseases and pests

• Drying out: Dried-up twigs after a dry summer. Bog bilberry needs wet feet: choose a wet spot or give rainwater.
• Lime: Yellow, sickly plants caused by limy soil or tap water. Only use rainwater.
• Grass invasion: Grasses such as purple moor-grass and birch seedlings crowd it out. Weed them out while young.
• Shade: Straggly growth and few flowers and berries. Move it into full sun.

Through the year

• March: Prune if needed; planting.
• April: Last month for pruning; weed out grasses and tree seedlings.
• May: Flowering begins: bells for bumblebees.
• July: Give rainwater in dry spells; take cuttings.
• August: Blue berries ripen.
• September: Last berries; planting possible.
• October: Red autumn colour; planting.

What can you use it for?

For wildlife

Typical of raised bogs and wet heath; bumblebees visit the flowers.

Food and drink

The berries are edible but bland.

Edible and useful

Berries (July–September)

Pick the berries from July to September, on a dry day, when they are entirely blue with a white bloom and feel slightly soft. Pick them by hand, one at a time; the little bushes grow slowly, so take only some and leave the rest. Bog bilberries are edible but bland: cook them with a sharper fruit such as apple, lemon or redcurrant. The flesh is white to pale green and does not stain your fingers, unlike bilberry. Use only sound, ripe berries.

Storing

Firm and unwashed, the berries keep for a week in the fridge in an open container. You can also wash them, dry them well, open-freeze them on a tray and then tip them into a bag; they stay good for a year that way. Jam keeps for a year in sterilised jars, syrup for six months in sterilised bottles.

Caution: Do not confuse bog bilberry with the poisonous herb Paris (Paris quadrifolia), a plant with four leaves in a cross and a single blue-black berry, or with deadly nightshade (Atropa belladonna), a large plant with glossy black berries in a star-shaped calyx. Bog bilberry is a bush up to 1 m tall with small, oval, blue-grey leaves with smooth edges; it looks most like bilberry, which has green, toothed leaves and purple flesh. Its German name ‘Rauschbeere’ (intoxicating berry) comes from the idea that large amounts cause dizziness or nausea, probably because of a fungus on the berries. So eat only modest amounts, use sound berries only, and throw away any that are mouldy, shrivelled or discoloured. Bog bilberry is rare in Flanders and grows on protected wet heath and raised bog: never pick in nature reserves, and preferably harvest from a plant in your own garden. Wild berries grow close to the ground: wash them thoroughly or heat them, because of the small risk of fox tapeworm eggs. Never eat anything you have not identified with certainty.

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

Recipes

• Bog bilberry and apple compote (Compote · ± 600 g, serves 4 · 25 min)
• Bog bilberry jam with lemon and vanilla (Jam · ± 3 jars of 250 ml · 40 min)
• Bog bilberry pancakes (Dish · ± 8 pancakes · 35 min)
• Bog bilberry syrup (Syrup · ± 500 ml · 30 min + 1 hour draining)

Did you know?

• In German it is called ‘Rauschbeere’ (intoxicating berry): eating a lot of them was said to make you dizzy. Today this is rather blamed on a fungus on the berries.
• Bog bilberry grows all around the North Pole, far into the tundra and high in the mountains. In Belgium it is very rare; one of the places to find it is the High Fens.