Bicoloured barrenwort

Bicoloured barrenwort: how do you recognise it?

Habit

Low, carpeting perennial 25–30 cm tall that slowly spreads by rhizomes to 40–60 cm and more.

Leaves

Made up of heart-shaped, slightly leathery leaflets on thin stalks; red-marked when young, green in summer, bronze to reddish brown in autumn and winter.

Flowers

Small, nodding flowers about 2 cm across with short spurs, in loose sprays on wiry stems, in April–May.

Colour

In ‘Sulphureum’, pale yellow with a deeper yellow centre.

Roots

Tough, creeping rhizomes just below the surface that compete well with tree roots.

Flowering: April–May · Plants: March–April and September–October · Pruning: February

Why grow it?

• One of the few ground covers that thrives in dry shade under trees.
• Attractive in every season: red-marked young leaves, yellow flowers in April, green in summer and bronze in winter.
• Forms a dense carpet where weeds have little chance.
• Semi-evergreen: the leaves largely stay until you cut them off in February.
• Low maintenance: one cut a year and hardly any other care.

Bicoloured barrenwort: where does it grow best?

• Partial shade to shade; in full sun the leaves scorch.
• Humus-rich loam or clay, acid to neutral; leaf mould works wonders.
• Moist to dry: once established it copes well with drought under trees, but not with waterlogging.
• Ideal under trees and shrubs, at the foot of a north-facing wall or among other shade plants.
• Plant 30–40 cm apart, about 7–9 plants per m² for a closed carpet.

Light

Partial shade and shade

Soil type

Loam or clay

Acidity

Acid or neutral

Moisture

Dry or normal

Size

0.3 m tall, 0.6 m wide

Hardiness

Hardy (to -30 °C)

Goes well with

• Ferns: Grow in the same shade; their fine fronds contrast with the heart-shaped leaflets.
• Hellebore: Also evergreen, a shade plant that flowers just before the barrenwort.
• Lungwort: Flowers at the same time; blue and pink beside the sulphur yellow.
• Snowdrop: Flowers in February, just after you have cut back the old leaves.
• Hosta: Big leaves beside the fine carpet, in summer shade.

Bicoloured barrenwort: when and how to plant it?

Plant in March–April and September–October.

1. Plant in March–April or in September–October.
2. Loosen the soil and work in a few spadefuls of leaf mould or well-rotted compost, especially under trees.
3. Set the plant at the same depth as in the pot: the rhizomes should sit just below the surface.
4. Space plants 30–40 cm apart.
5. Water well straight away, and regularly in dry spells during the first year.
6. Spread a layer of leaf mould or fine bark chips around the plants.

Care

Water

Regularly in dry weather during the first year. After that only in long dry summers, especially under trees.

Feeding

A layer of compost or leaf mould in March, after cutting off the old leaves, is enough.

Mulching

Let fallen tree leaves lie between the plants in autumn: they form a natural mulch.

Old leaves

In February, cut all the old leaves down to the ground so the flowers and young foliage show well.

Division

Not needed; divide only if you want more plants or the carpet becomes bare in the middle.

Tip: Under trees, water it regularly in its first year and give it a layer of leaf mould every spring: once established it looks after itself, even in dry shade.

Bicoloured barrenwort: when to prune it?

Pruning months: February.

When: In February, before the new flower stems push through the soil.

How:

• Cut all the old leaves to just above ground level with shears or a hedge trimmer.
• On large areas you can also carefully use a mower on its highest setting, when the ground is dry.
• Rake away the cut leaves, then spread a thin layer of leaf mould.

Caution: Don’t leave it too late: by early March the flower stems are already hidden among the old leaves and are easily cut off with them.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Autumn division

In September, lift a piece of the clump, cut the rhizomes with a knife or spade into pieces each with a few buds, and replant at once.

Spring division

It can also be done after flowering, in May; water the divisions regularly through the summer.

Bicoloured barrenwort: how does it get through the winter?

Hardy to −30 °C.

• Fully hardy, to about −30 °C: in Belgium it needs no protection.
• The leaves largely stay and turn bronze; they protect the crown until you cut them in February.
• In hard frost or cold wind the leaves may brown. That is purely cosmetic.
• In a pot: keep it in shade against a wall and wrap the pot in hessian during hard frost.

Diseases and pests

• Vine weevil: Half-moon notches in the leaf edges; the grubs eat the roots, especially in pots. Apply nematodes against the grubs in late summer.
• Brown leaf edges: Drought in the first year or too much sun. Water and choose a shadier spot.
• Slugs: Eat the young leaves in spring. Pick them off in the evening or set beer traps.
• Flowers hidden: The old leaves were not cut and hide the flowers. Cut them in February next year.

Through the year

• February: Cut old leaves to the ground before the flower stems appear.
• March: Plant. Spread leaf mould.
• April: In flower, together with the red-marked young leaves.
• May: Flowering ends. Division possible now.
• June: Leaves turn green. Water young plants in dry spells.
• August: If vine weevil is a problem, apply nematodes.
• September: Plant and divide.
• October: Plant. Leave fallen tree leaves as mulch.
• November: Leaves turn bronze and largely stay.

Did you know?

• Barrenworts belong to the barberry family, Berberidaceae, which you would never guess from this low shade plant.
• Epimedium × versicolor is a hybrid between the Japanese Epimedium grandiflorum and a Caucasian subspecies of Epimedium pinnatum.
• Another English name for epimediums, ‘bishop’s hat’, refers to the shape of the flower.