Hinoki cypress

Hinoki cypress: how do you recognise it?

Growth habit

Conical tree up to about 15 m tall and 5 m wide; the many dwarf forms stay globe- or cone-shaped and are 0.5–2 m tall.

Foliage

Tiny scale-like leaves in flat, wavy, shell-like sprays; glossy dark green or gold, with white markings beneath.

Bark

Reddish brown, peeling thinly in fibrous strips.

Cones

Small, round cones about 1 cm across.

Scent

A soft, resinous and aromatic scent, with a hint of citrus, from the sprays and the wood.

Plants: April–May and September–October · Pruning: May–June

Why grow it?

• Attractive all year: evergreen, with shell-like sprays in glossy green or gold.
• Dwarf forms suit small gardens, rock gardens, Japanese gardens and large pots.
• Little work: it grows slowly and hardly needs pruning.
• A calm, sculptural outline that works well beside Japanese maples and rhododendrons.
• Fully hardy to about −30 °C.

Hinoki cypress: where does it grow best?

• Sun to partial shade; the golden cultivars in particular colour best in sun but scorch in full heat.
• Cool, humus-rich, free-draining soil: sand or loam; acid to neutral, lime-free. It dislikes lime.
• Evenly moist soil; it tolerates neither prolonged drought nor wet feet.
• Sheltered from dry, cold wind, which turns the sprays brown. Allow 4–5 m for the species; 1–2 m for dwarf forms.

Light

Sun and partial shade

Soil type

Sand or loam

Acidity

Acid or neutral

Moisture

Normal

Size

15 m tall, 5 m wide

Hardiness

Hardy (to -30 °C)

Goes well with

• Japanese maple: Soft autumn colours next to the evergreen, shell-like foliage.
• Rhododendron and Japanese azalea: They like the same cool, acid soil and flower in spring.
• Pieris: An evergreen shrub with spring flowers on the same acid soil.
• Hosta: A foliage plant for partial shade at the foot of the conifer.

Hinoki cypress: when and how to plant it?

Plant in April–May and September–October.

1. Plant in April–May or in September–October, when the soil is neither frozen nor bone dry.
2. Dig a hole twice as wide as the rootball and just as deep; mix in a few spadefuls of compost.
3. Set the tree at the same depth as in the pot and firm the soil well; do not bury the trunk.
4. Water thoroughly at once and then weekly in dry weather for the first two years.
5. Spread a layer of bark or leaf-mould mulch around the base and stake tall specimens if needed.

Care

Water

For the first two years weekly in dry weather, soaking well. After that only in prolonged drought, including in winter during dry frosts.

Feeding

In March–April, a handful of organic feed or a special conifer feed low in nitrogen. Not too much: it prefers to grow slowly.

Mulching

A layer of bark or leaf mould keeps the roots cool and moist and suppresses weeds.

Lime

Do not give lime or hard water; use rainwater for potted plants where possible.

In pots

Dwarf forms do well in a large pot with loose, acid compost; repot every 3–4 years.

Tip: Give it cool, lime-free soil and a spot sheltered from dry wind. Prune only in the young green growth: it does not regrow from old, bare wood.

Hinoki cypress: when to prune it?

Pruning months: May–June.

When: Rarely needed. If necessary, trim lightly in May–June, in the young green growth.

How:

• Shorten only the young, green shoot tips a little to keep the shape.
• Remove dead, dry and damaged sprays.
• Remove shoots that differ from the cultivar, for example a green shoot on a golden tree.
• Leave the natural shape: a globe or cone is seldom clipped tightly.

Caution: Never cut into old, bare wood: it does not regrow from there. Always keep green foliage on the branch.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Cuttings

From August to October: take semi-ripe cuttings of 10–15 cm with a heel of old wood, set them in sandy compost and keep them moist and frost-free. Roots follow after a few months.

Seed

The species can be grown from seed, but seedlings grow slowly and cultivars do not come true from seed. Cultivars are usually propagated by cuttings or grafting.

Hinoki cypress: how does it get through the winter?

Hardy to −30 °C.

• Fully hardy to about −30 °C: no protection is needed in open ground.
• Shelter newly planted and young specimens from cold, dry wind with a hessian screen.
• Water during a dry frost on a frost-free day: evergreens also lose water in winter.
• In a pot: wrap the pot in bubble wrap or hessian and stand it against a wall.

Diseases and pests

• Brown sprays in spring: Winter damage from dry wind or frozen soil. Cut brown sprays back to the green, mulch and water in dry weather.
• Brown inside: Old inner sprays drop naturally in autumn. This is normal; shake or brush them out and make sure the outside stays green.
• Root rot: Whole branches turn yellow or brown in heavy, wet soil. There is no cure. Plant in a free-draining spot, if need be on a raised mound.
• Spider mites: Dull grey, faded foliage and fine webbing in warm, dry summers. Spray the branches with water and provide humidity around the plant.

Through the year

• January: Gently shake heavy, wet snow off the branches.
• February: Check for winter damage. Do not prune yet.
• March: Apply organic or conifer feed.
• April: Plant. Mulch.
• May: Plant. Trim lightly, only in the green growth.
• June: Trim lightly. Water in dry weather.
• July: Water young plants in dry weather.
• August: Watch for spider mites. Take cuttings.
• September: Plant. Take cuttings.
• October: Plant. Top up the mulch.
• November: Protect the pot from frost.
• December: Rest. Water during dry frost on a frost-free day.

Did you know?

• In Japan the light, fragrant wood of the hinoki has been used for centuries for temples, shrines and bathtubs.
• The species name ‘obtusa’ means blunt and refers to the blunt tips of the scale-like leaves.
• Some dwarf forms grow only a few centimetres a year and are also grown as bonsai.