Yellow archangel

Yellow archangel: how do you recognise it?

Habit

Loose mat about 30 cm tall, with upright flower stems and long, creeping runners of 1 m or more.

Leaves

Oval, toothed and opposite, green; with silver patches in the garden form. In mild winters some leaves stay on.

Flower

Bright yellow, two-lipped flowers with reddish-brown markings, in whorls in the leaf axils, April to June.

Stem

Square, as in all members of the mint family; the runners root where they touch the ground.

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

Why grow it?

• Grows in deep shade, even under trees, where hardly anything else flowers.
• Native and valuable for bumblebees and other bees in spring.
• Quick ground cover for bare, shady patches and banks.
• Bright yellow flowers in April–June bring light to a dark corner.
• Fits perfectly in a wildlife garden or woodland edge, alongside other native woodland plants.

Yellow archangel: where does it grow best?

• Partial or full shade; in full sun the leaves scorch and the plant dries out.
• Almost any humus-rich soil: sand, loam or clay, acid to chalky.
• Moderately moist; once established it also tolerates some dryness under trees.
• Do not plant it next to woodland or a nature reserve, or among small, delicate plants.
• Allow 40–60 cm between plants; the mat closes quickly.

Light

Partial shade and shade

Soil type

Sand, loam or clay

Acidity

Not fussy

Moisture

Normal

Size

0.3 m tall, 1 m wide

Hardiness

Hardy (to -30 °C)

Goes well with

• Wood anemone: White spring flowers at the same woodland edge; in the wild they often grow together.
• Bluebell: Blue flowers at the same time as the yellow archangel, under trees.
• Ferns: Fine green fronds above the low mat.
• Holly: An evergreen shrub under which it covers the ground.

Yellow archangel: when and how to plant it?

Plant in March–April and September–October.

1. Plant in March–April or September–October, when the soil is neither frozen nor waterlogged.
2. Loosen the soil and mix in some leaf mould.
3. Set the plant at the same depth as in its pot and firm the soil.
4. Space plants 40–60 cm apart.
5. Water straight away and again during dry spells in the first year.
6. Choose a spot bounded by a path, a wall or a mown lawn, so you can keep it in check.

Care

Watering

Only in dry spells during the first year; rarely needed after that.

Feeding

Not needed: rich soil makes it even more vigorous.

Cutting back

After flowering, in July, cut back the flower stems and long runners for a compact mat.

Controlling runners

Each year, pull up or chop off runners that grow beyond their space.

Garden waste

Never dump pulled-up pieces in the countryside: they root again easily.

Tip: Only plant the silver-leaved form where it is allowed to spread, for example under large shrubs between a path and a wall; the wild, green-leaved form is less aggressive.

Yellow archangel: when to prune it?

Pruning months: July.

When: In July, after flowering, cut the plant back. Remove runners that go too far whenever you see them.

How:

• Cut spent stems and long runners back to about 10 cm.
• For large areas, shears or a mower on its highest setting work well.
• Chop back the edge of the mat with a spade in spring and late summer.

Caution: Do not dump clippings or pulled-up plants in woodland or on verges: pieces of stem will root.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Runners

The easiest way: in spring or late summer, cut off a rooted runner and plant it elsewhere.

Division

In March–April or September, cut a piece from the mat with a spade and replant it straight away.

Cuttings

In summer, tip cuttings of non-flowering shoots root quickly in moist cutting compost.

Yellow archangel: how does it get through the winter?

Hardy to −30 °C.

• Very hardy, to about −30 °C: no protection is needed in Belgium.
• In mild winters some leaves stay on, especially in the silver-leaved form.
• Leave fallen tree leaves where they lie: it grows through them in spring.

Diseases and pests

• Spreading: The silver-leaved form in particular smothers its neighbours. Cut back after flowering and chop back the edge every year.
• Scorched leaves: Brown patches in sun or drought. Plant it in shade and water during long dry spells.
• Powdery mildew: White powder on the leaves in dry summers. Cut the plant back: fresh leaves will follow.
• Bare patches: Old mats open up in the centre. Cut back and fill in with rooted runners.

Through the year

• March: Plant or divide. Chop back the edge of the mat.
• April: Flowering begins. The first bumblebees visit.
• May: Full flower.
• June: Last flowers.
• July: Cut back after flowering. Control runners.
• August: Remove runners that go too far. Take tip cuttings.
• September: Plant or divide. Chop back the edge.
• October: Plant. Move rooted runners.
• December: Partly green leaves in mild winters.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Did you know?

• Although its leaves look like those of a stinging nettle, a dead-nettle does not sting: hence the name.
• In Flanders and Britain the wild yellow archangel is regarded as a typical plant of ancient woodland.
• In Britain the silver-leaved form is on the list of plants that it is an offence to plant or allow to grow in the wild.