Licorice plant

Licorice plant: how do you recognise it?

Habit

Loose, sprawling plant about 40 cm high with long creeping or trailing stems up to roughly 1 m.

Leaves

Rounded to oval or heart-shaped, 2–4 cm long, densely felted and silver-grey; lime-green in ‘Limelight’.

Flower

Small, inconspicuous cream flowerheads, rarely seen in our gardens; the plant is grown for its foliage.

Hairs

Stems and leaves are covered in dense, woolly hairs that protect against sun and drying out.

Roots

Fine and shallow; the plant needs free-draining soil and dislikes wet feet.

Plants: May–June · Pruning: May–August

Why grow it?

• Silver-grey foliage that stays attractive all summer and makes bright colours stand out.
• A strong filler: one plant quickly covers a large container or hanging basket with its long, trailing stems.
• Tolerates sun and drought, ideal for containers on a south-facing wall or patio.
• Combines with almost every summer-flowering plant, from pelargonium to petunia.
• Easy to overwinter as cuttings, giving you free new plants next year.

Licorice plant: where does it grow best?

• Full sun for the best silver-grey foliage; in shade the plant becomes thin and greenish.
• Free-draining, rather poor to ordinary soil: sandy or loamy, acid to chalky. In containers use potting compost with some sand or perlite.
• Dry to average moisture: the plant tolerates drought well, but not waterlogged soil.
• Allow 40–50 cm between plants in a border; in a container or basket one plant is often enough as a filler.

Light

Sun

Soil type

Sand or loam

Acidity

Not fussy

Moisture

Dry or normal

Size

0.4 m tall, 1 m wide

Hardiness

Tolerates light frost (to -2 °C)

Goes well with

• Pelargonium: Bright red or pink flowers beside the silver-grey foliage, both loving the sun.
• Petunia: Rich flowering in containers, with the silver as a calm contrast between them.
• Verbena: Purple or red flowers that stand out beautifully against the felted leaves.
• Salvia: Blue flower spikes that complement the silver stems.
• Lobelia: A blue edging in containers, beneath the silver-grey foliage.

Licorice plant: when and how to plant it?

Plant in May–June.

1. Plant out in May–June, when night frost is no longer expected; it tolerates only the lightest frost, around −2 °C.
2. Ease the plant out of its pot without breaking up the rootball.
3. Set it at the same depth as in the pot, in free-draining soil or in a container with drainage holes.
4. Leave 40–50 cm between plants in a border; in a container, put one plant at the edge among the flowers.
5. Water well after planting, then let the soil dry out slightly.
6. Pinch the stems back a little straight away so that the plant branches and grows denser.

Care

Water

Moderate. Let the soil dry out between waterings and water at the base, not over the felted leaves.

Feeding

In containers, a weak dose of liquid feed every two to three weeks; too much feed produces limp, thin stems.

Pinching

Shorten long stems to the length you want and pinch the tips: the plant stays dense and compact.

Mulching

Not needed in containers; in a border a thin layer of grit or bark keeps the foliage dry and clean.

Support

Not needed: the stems trail or lie on the ground.

Tidying

Remove dried or brown leaves and stems, especially in late summer, to prevent mould.

Tip: Pinch or cut back the stems regularly so it stays dense and compact instead of bare and thin. Take cuttings in September to overwinter it for free.

Licorice plant: when to prune it?

Pruning months: May–August.

When: From May to August: cut it back when the stems grow too long or become bare.

How:

• Cut off the tips of long stems just above a leaf so that side shoots form.
• Remove dried, brown or bare stems completely.
• A hard cut back by half is fine, as long as green leaves remain on the stem.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Late-summer cuttings

In August–September: take 8–10 cm tip cuttings, remove the lower leaves and insert in sandy potting compost. Keep them bright at 15–20 °C; they root in 3–4 weeks.

Spring cuttings

In March–April from an overwintered plant: take tip cuttings and root them. This gives you new plants in good time for May.

Licorice plant: how does it get through the winter?

Hardy to −2 °C: protect in harsh winters.

• Not hardy: it tolerates only the lightest frost, around −2 °C, and is grown as an annual in our region.
• To keep it, take cuttings in September and overwinter them in a bright, frost-free room at 5–10 °C with very little water.
• Overwintering potted plants: keep them dry and bright, otherwise the foliage rots.

Diseases and pests

• Grey mould and rot: In cool, damp periods the felted foliage rots. Water at the base, allow space and remove affected parts.
• Whitefly and aphids: Sap-sucking insects under the leaves and on young shoots. Wash off with water, use yellow sticky traps or let ladybirds deal with them.
• Thin, bare stems: Caused by too little light or too much feed. Move it into more sun, feed less and shorten the long stems.
• Brown leaves: Caused by frost, overwatering or scorch. Let the soil dry out and remove the brown leaves.

Through the year

• March: Take cuttings from overwintered plants.
• April: Root the cuttings and harden them off.
• May: Plant out after the ice saints. Pinch back.
• June: Plant out in containers. Water moderately.
• July: Cut back if it grows too long. Feed weakly every 2–3 weeks in containers.
• August: Cut back. Take cuttings for overwintering.
• September: Take cuttings and root them.
• October: Bring mother plants or cuttings indoors, frost-free.

Did you know?

• In its South African homeland, Helichrysum petiolare is an evergreen shrub, not an annual: here it is grown that way because it cannot tolerate hard frost.
• The dense white felt is made of fine hairs that protect the foliage from sun and drying out.
• With its silver-grey foliage, it has long been a classic in summer containers and hanging baskets.