Mistletoe

How to recognise it

Habit

Round, evergreen shrublet 30–100 cm across, high up in the branches of a tree.

Stem

Green, smooth and jointed; it forks into two again and again, which creates the typical ball shape. Snaps easily at the joints.

Leaf

Opposite, narrowly oval to strap-shaped, 2–8 cm, thick and leathery, yellowish green, without teeth.

Flower

Tiny, yellowish green and inconspicuous, in small clusters in the forks of the twigs, from February to April. Male and female flowers grow on separate plants.

Fruit

White, translucent berry of 6–10 mm with tough, sticky flesh and a single seed; ripe in November–December and long-lasting.

Roots

No true roots: a sucker (haustorium) grows into the wood of the host and taps water and minerals from it.

Confusion with

From a distance, witches’ brooms (dense clusters of twigs caused by a fungus, especially in birch) and birds’ nests look like mistletoe, but they are not green in winter.

Flowering: February–April · Pruning: December–February

Why grow it?

• The white berries feed birds such as the mistle thrush and the blackcap in winter, just when other food is scarce.
• It flowers from February: the tiny flowers give flies and bees nectar and pollen early in the year.
• Evergreen: the green balls bring colour to bare trees.
• A plant steeped in folklore, from the druids to kissing under the mistletoe at Christmas and New Year.
• A remarkable way of life: it grows without ever touching the ground.
• Sprigs with berries make lovely Christmas decorations from your own orchard.

Mistletoe: where does it grow best?

• In the wild on trees with soft bark: mainly apple, poplar, lime, hawthorn, willow and false acacia; rarely on oak.
• It seeks light: on the outside of the crown, in orchards, rows of trees, parks and along roads.
• It does not choose its host: birds leave the seeds where they perch, often in a solitary tree they use as a lookout.
• In the garden: on a healthy, mature apple, hawthorn or lime, on a well-lit branch at least 20 cm in girth.

Goes well with

• Standard apple tree: The classic orchard host, with soft bark on which the seeds germinate well.
• Common hawthorn: A native host that also gives blossom and berries for birds.
• Small-leaved lime: A large, airy crown in which mistletoe thrives.
• Poplar: Along streams and avenues, a host on which mistletoe grows very well.
• Holly: Together with mistletoe the classic Christmas greenery; its berries also feed birds.

Mistletoe: when and how to plant it?

1. You cannot buy mistletoe in a pot: you sow it straight onto a tree. Use fresh, fully ripe berries from February to April, preferably from the same kind of tree as yours.
2. Choose a healthy, well-lit branch at least 20 cm in girth, high enough not to bump into.
3. Squeeze the berry and press the sticky seed against the bark, in a crack or on the underside of the branch, where birds are less likely to find it. There is no need to cut the bark: the sticky pulp glues the seed in place.
4. Place 10–20 seeds in different spots: only a small share germinates, and you need male and female plants for berries.
5. Be patient: in the first year you only see a small green bump, the first leaves after two or three years and berries after four or five years.
6. Do not take mistletoe from trees in the countryside or from other people’s trees without permission; use berries from your own garden or from someone happy to share.

Care

Host tree

A healthy host is the best care: water the tree in dry spells and leave the soil beneath it undisturbed.

Watering and feeding

Not needed: mistletoe takes everything it needs from the tree.

Thinning

Too many clumps weaken a tree. Remove some in winter, especially on old fruit trees.

Harvesting

Cut sprigs with berries in December for indoors; leave plenty for the birds.

Broken branches

Large clumps catch a lot of wind and snow: after a storm, check that the branch is still sound.

Tip: Collect berries for sowing in February or March, when they are truly ripe. Berries from a Christmas sprig are often not ripe enough to germinate.

Pruning and mowing

Pruning months: December–February.

When: In winter, from December to February, when the tree is bare and the clumps are easy to see.

How:

• Cut out clumps that grow too large or too close together at their base.
• The sucker stays in the branch and regrows. To get rid of a clump completely, saw off the branch about 30 cm below where it is attached.
• On a large tree, always leave a few clumps for the birds and for next year’s berries.
• Use a sturdy ladder or a pole saw and never work alone high up in a tree.

Caution: Too much mistletoe weakens old fruit trees: thin it out in good time rather than removing everything at once.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Seed

From February to April, press ripe berries onto a branch of a host tree. Germinates in spring, first leaves after two years.

Birds

The natural way: thrushes and blackcaps eat the berries and leave the sticky seeds on branches. A tree where birds like to perch often gets mistletoe by itself.

Mistletoe: how does it get through the winter?

Hardy to −25 °C.

• Evergreen: in winter the green balls stand out most in the bare crowns.
• The berries ripen in November–December and stay well into winter: important food for thrushes and blackcaps.
• Fully hardy in Belgium, to about −25 °C.
• The best time to thin it out and cut sprigs for Christmas.

Diseases and pests

• No germination: Seeds are eaten by birds or dry out. Place more, on several branches, and use fresh, ripe berries.
• No berries: Only female plants bear berries, and only if a male plant grows nearby. So always sow several seeds.
• Weakened tree: Too many clumps take up a lot of water and branches die back. Thin out every winter.
• Breaking branches: Heavy clumps on thin branches snap in storms or under wet snow. Remove them in time.

Through the year

• January: Berries still hanging: watch for thrushes and blackcaps. Thin out if needed.
• February: Flowering begins. Press ripe berries onto a host tree. Thinning still possible.
• March: Flowering. Place seeds on branches.
• April: End of flowering. Last berries to sow.
• May: New shoots appear.
• August: Young green berries form.
• October: The berries turn white.
• November: Berries ripe. Check branches after the first storms.
• December: Cut sprigs for Christmas. Thin out.

Did you know?

• The mistle thrush is called Turdus viscivorus in Latin, ‘mistletoe-eater’: in winter it sometimes defends a whole tree full of mistletoe against other birds.
• According to the Roman writer Pliny the Elder, druids cut mistletoe from oaks with a golden sickle. Mistletoe on oak is rare, which made it so special.
• Viscum is Latin for birdlime: the sticky berries were once used to make glue for catching birds.