Tree heath

Tree heath: how do you recognise it?

Habit

Upright, densely branched shrub of 1.5–2 m in gardens, sometimes 4–5 m in the wild.

Leaf

Needle-like, 3–5 mm, in whorls of three or four around the stem; fresh green or golden in some forms.

Flower

Small, white, rounded bells of 2–4 mm in dense panicles, from March to May.

Scent

Sweet honey scent, especially on sunny days.

Roots

A heavy woody root burl (briar) once used to make pipes.

Flowering: March–May · Plants: April–May · Pruning: May–June

Why grow it?

• A cloud of white, honey-scented flowers from March to May.
• One of the first big nectar sources in spring for honeybees and bumblebees.
• Evergreen: fine, fresh green foliage that gives structure in winter too.
• Adds height to a heather garden or a Mediterranean border.
• Tolerates drought and poor, acid soil once well established.

Tree heath: where does it grow best?

• Full sun for the best flowering.
• Sheltered from cold, drying east and north winds.
• Acid to neutral, free-draining soil: sand or light loam; no wet clay.
• Does not tolerate chalky soil: the leaves turn yellow.
• Plant 1–1.5 m from other shrubs.

Light

Sun

Soil type

Sand or loam

Acidity

Acid or neutral

Moisture

Dry or normal

Size

2 m tall, 1.5 m wide

Hardiness

Hardy (to -15 °C)

Goes well with

• Lavender: Likes the same sun and dry, free-draining soil.
• French lavender: Flowers just after the tree heath and brings purple to a Mediterranean corner.
• Rockrose: Another Mediterranean shrub for a sunny, dry spot.
• Ling heather: Low heather at its feet for a heather garden that flowers in summer.
• Pine: A small pine gives shelter and suits the same acid conditions.

Tree heath: when and how to plant it?

Plant in April–May.

1. Plant in April or May so the shrub is well rooted before winter.
2. Improve heavy soil with sand and acid compost or leaf mould; add a drainage layer if needed.
3. Set the root ball at the same depth as in the pot; planting too deep makes the stem rot.
4. Water well and keep the soil slightly moist during the first year.
5. Mulch with pine needles or bark to keep the soil acid and cool.

Care

Water

In dry spells during the first year; after that it is fairly drought tolerant.

Feeding

Little needed: some acid compost or ericaceous fertiliser in spring.

Mulching

Pine needles or bark keep the soil acid and protect the roots.

Shelter

Protect young plants in severe winters with fleece against cold wind.

Lime

Avoid tap water in hard-water areas; use rainwater.

Tip: Plant tree heath in the lee of a wall or taller shrubs: sheltered from cold wind, it flowers far more freely and keeps its foliage a fine green.

Tree heath: when to prune it?

Pruning months: May–June.

When: After flowering, in May–June.

How:

• Lightly trim the faded panicles to keep the shrub compact.
• Never cut into old, bare wood: tree heath regrows from it poorly.
• Remove frost-damaged branches only in spring, when you can see where new shoots appear.

Caution: Do not prune in autumn or winter: you would lose the flower buds.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Semi-ripe cuttings

In July–August: 5 cm cuttings in a mix of peat-free ericaceous compost and sand, under plastic.

Seed

Possible but slow; the ornamental forms do not come true from seed.

Tree heath: how does it get through the winter?

Hardy to −15 °C: protect young plants.

• Hardy to about −15 °C in a sheltered spot with free-draining soil.
• Evergreen: the shrub stays green all winter.
• Cold, waterlogged soil is more dangerous than frost: make sure drainage is good.
• Protect young plants with fleece in hard frost and cold wind.

Diseases and pests

• Yellow leaves: Soil or water that is too chalky. Use rainwater, acid compost and if needed iron chelate.
• Brown branches: Frost or wind damage. Cut back to healthy wood in spring.
• Root rot: Caused by waterlogging. Plant in free-draining soil, raised if necessary.

Through the year

• March: Start of flowering. Mulch.
• April: Full flower: enjoy the bees. Planting.
• May: End of flowering. Trim lightly. Planting is still possible.
• June: Last pruning jobs. Water in dry spells.
• July: Take semi-ripe cuttings.
• August: Water during long dry spells.
• November: Have fleece ready for young plants.
• December: Protect young plants in hard frost.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Did you know?

• The hard root burl of tree heath, ‘bruyère’ in French, has long been carved into tobacco pipes: the famous briar pipes.
• In its native range, tree heath sometimes grows into a real small tree more than 5 m tall.