🌸 Cercidiphyllum japonicum ‘Hanna’s Heart’ – Hanna's Heart Katsura

🔎 Identification

Scientific name: Cercidiphyllum japonicum ‘Hanna’s Heart’

Family: Cercidiphyllaceae.

Common names: Katsura, caramel tree, cake tree, Hanna's Heart katsura.

Species origin: Japan and China.

Cultivar origin: American horticultural selection introduced by Biringer Nursery.

Type: Deciduous ornamental tree.

Special feature: Selected for a narrow, upright habit, heart-shaped foliage and better cold resistance than some traditional katsuras.

🌿 Botanical description

Habit: Upright, narrow, compact and slightly pyramidal.

Height: About 7 to 8 m at maturity.

Spread: About 2 to 3 m, sometimes more depending on conditions.

Growth: Moderate, generally slower than the species.

Trunk: Straight, with relatively dense branching.

Branches: Upright, forming a slender crown.

Leaves:

• Rounded to cordate (heart-shaped).

• Dark green to blue-green in summer.

• Soft, slightly satiny texture.

• Opposite or sometimes nearly opposite arrangement.

• Spring foliage sometimes tinged red or bronze.

Bark: Greyish brown, gradually becoming more textured with age.

🌸 Flowering

Period: April to May, depending on the climate.

Flowers:

• Very small and inconspicuous.

• Reddish to pinkish.

• Appear before or at leaf bud break.

• Can go almost unnoticed.

Special feature: Katsura is dioecious: male and female flowers are generally borne on separate trees. Flowering is not its main ornamental attraction.

🍃 Foliage and fall fragrance

A remarkable katsura feature: Foliage releases a very pleasant sweet scent in fall, especially as leaves yellow and drop.

Fall colours:

• Bright golden yellow.

• Apricot orange.

• Sometimes pinkish shades.

• Colour is generally more intense when nights are cool.

Fragrance: Fallen leaves can smell of caramel, burnt sugar, cotton candy or even pastries.

🍬 This distinctive scent earned it the nickname “caramel tree.”

🌱 Growing conditions

Exposure: Full sun to partial shade.

Soil: Rich, deep, fertile, moist and well drained.

Texture: Prefers loamy or humus-rich soils.

pH: Slightly acidic to neutral, but tolerates different pH levels.

Moisture: Prefers consistently moist soil without waterlogging.

Watering: Regular, especially during droughts and the first few years after planting.

Planting: Spring or fall.

Spacing: Allow about 3 to 4 m between trees for its narrow habit, more for unrestricted development.

Location: Choose a spot sheltered from drying winds.

Special feature: Tolerates prolonged drought less well than some ornamental trees. Moist soil encourages attractive foliage.

❄️ Hardiness

Zones: 4 to 8.

Approximate minimum temperature: Around -30 °C, depending on growing conditions and how well established the tree is.

Winter resistance:

• ‘Hanna’s Heart’ is considered hardier than some traditional katsura selections.

• Has better cold resistance and less twig dieback.

• Generally retains foliage later into fall.

• Young trees benefit from protection against cold winds.

Special feature: Improved hardiness was one of this cultivar's selection criteria.

✂️ Care

Pruning: Generally unnecessary. Prune lightly only to remove dead, diseased or poorly positioned branches.

Pruning period: Late fall after leaf drop or late winter.

Fertilizing: Well-rotted compost in spring if soil is poor.

Mulching: Recommended to retain moisture and protect shallow roots.

Watering: Monitor especially during hot, dry weather.

Propagation: Mainly by grafting to preserve cultivar characteristics.

Transplanting: Can be difficult once established; avoid unnecessary root disturbance.

Diseases and pests: Generally few problems, but monitor water stress and leaf scorch.

🦋 Ecological value

• Branching provides shelter for birds.

• Inconspicuous flowers may contribute to insects' food resources.

• Provides useful plant cover during the growing season.

• Adds to the diversity of ornamental trees in the garden.

✅ Highlights

• Beautiful narrow, vertical habit.

• Ideal for relatively limited spaces.

• Distinctive heart-shaped leaves.

• Very elegant dark green foliage.

• Yellow and apricot fall colours.

• Characteristic caramel scent in fall.

• Hardier than some traditional katsuras.

• Moderate growth.

• Little pruning required.

• Ornamental interest across several seasons.

❌ Points to consider

• Needs sufficiently moist soil.

• Sensitive to prolonged drought.

• May develop leaf scorch in hot, dry weather.

• Relatively slow growth.

• Sometimes difficult to transplant.

• Inconspicuous flowering.

• Mature spread may exceed stated dimensions depending on growing conditions.

  🌳 Distinctive feature: ‘Hanna’s Heart’ is especially appealing where an elegant tree is wanted without taking up too much width. Heart-shaped foliage, a vertical habit and a caramel scent in fall make it an unusual, distinctive ornamental tree.