Prunus 'Kanzan', Kwanzan flowering cherry
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Broadleaf Deciduous Trees

Prunus 'Kanzan'

Kwanzan flowering cherry

RosaceaeCultivar of Japanese garden origin

At a Glance

TypeTree
HabitUpright
FoliageDeciduous
Height25-35 feet (7.6-10.7 m)
Width20-30 feet (6-9 m)
Maturity10 years

Growing Zones

USDA Hardiness Zones

5 - 8
Zone 5
Zone 6
Zone 7
Zone 8
These zones indicate the coldest temperatures this plant can typically survive.
Frost Tolerancehardy

Overview

Prunus 'Kanzan' is a deciduous tree reaching 25-35 feet (7.6-10.7 m) tall with a spread of 20-30 feet (6-9 m), developing a distinctive upright-vase to broadly vase-shaped crown that becomes more spreading with age. This is one of the most widely planted flowering cherry cultivars worldwide. Bark is smooth, reddish-brown to gray-brown with prominent horizontal lenticels. Leaves are alternate, simple, ovate to obovate, 3-5 inches (8-13 cm) long, with sharply serrate margins. Foliage emerges coppery-bronze to reddish-bronze, concurrent with bloom, providing a warm-toned backdrop for the flowers; summer color is dark green; fall color is variable, occasionally developing bronze to orange tones. Flowers are fully double with 20-30 petals, 2-2.5 inches (5-6 cm) across, deep pink, borne in pendulous clusters of 3-5 in April. Bloom is later than Yoshino cherries by 1-3 weeks. The double flowers are sterile and produce no fruit. Growth rate is moderate at 12-18 inches (30-46 cm) per year. Trees are short-lived at 15-25 years, with bacterial canker the primary cause of decline. The cultivar is also known as 'Sekiyama' and 'Kwanzan'. Grafted onto rootstock, usually Prunus avium; graft incompatibility occasionally causes failure at the union. Susceptible to bacterial canker, borers, cherry leaf spot, and tent caterpillars.

Native Range

Prunus 'Kanzan' is a cultivar of Japanese garden origin within the Sato-Zakura group, selected from complex hybrids involving Prunus serrulata and possibly other species over centuries of cultivation in Japan. The cultivar was documented in Japanese horticultural literature by the early 19th century.

Suggested Uses

Commonly planted as a specimen tree, street tree, and park tree for the spring flower display. Space 20-25 feet (6-7.6 m) from other trees and structures. The sterile double flowers produce no fruit, making it cleaner than fruiting cherries for use near sidewalks and patios. Short lifespan of 15-25 years requires planning for replacement. Widely planted in civic cherry blossom festivals and memorial plantings.

How to Identify

Identified by fully double deep pink flowers with 20-30 petals, 2-2.5 inches (5-6 cm) across, in pendulous clusters of 3-5 in April. Coppery-bronze emerging foliage appears concurrent with bloom. Upright-vase to broadly spreading crown form. Distinguished from Prunus 'Shirotae' by deep pink (not white) flowers and upright (not spreading) habit. Distinguished from Prunus x blireana by larger double flowers, green (not purple) summer foliage, and later bloom time.

Appearance

Size & Dimensions

Height25' - 35'
Width/Spread20' - 30'

Reaches mature size in approximately 10 years

Colors

Flower Colors

pink

Foliage Colors

green
bronze

Fall Foliage Colors

bronze
orange

Bloom Information

Bloom Period

~2 weeks
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Spring
Fully double deep pink flowers appear in April, typically 1-3 weeks after Yoshino cherries. In the Pacific Northwest, peak bloom usually occurs in mid- to late April, lasting 1-2 weeks depending on weather. Coppery-bronze emerging foliage provides a complementary backdrop. No fruit production, as double flowers are sterile.

Detailed Descriptions

Flower Description

Deep pink, fully double

Foliage Description

Dark green, emerging coppery-bronze

Growing Conditions

Sun Requirements

Full Sun
Requires 6-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range5.5 - 7.0(Neutral)
357912
Soil Types
loamsand
Drainage
well drained

Water & Climate

Water Needs

Medium

Frost Tolerance

hardy

Time to Maturity

3-5 years

Care & Maintenance

Care Guide

Water regularly during the first two growing seasons. Established trees benefit from supplemental water during dry periods exceeding 2-3 weeks. Plant in full sun with at least 6 hours of direct light. Requires well-drained soil; intolerant of waterlogged conditions. Site with good air circulation to reduce fungal disease pressure. Bacterial canker (Pseudomonas syringae) is the primary disease, causing branch dieback and progressive decline; prune only during dry weather. Check graft union periodically for signs of incompatibility, including bark cracking or dieback above the union. Borers attack stressed trees; maintain vigor with appropriate watering. Cherry leaf spot may cause premature defoliation in wet seasons.

Pruning

Prune in midsummer (June through July) during dry weather. Remove dead, damaged, and crossing branches. The natural vase-shaped form requires minimal corrective pruning. Avoid heavy cuts, as wounds heal slowly and provide entry points for bacterial canker. Remove any rootstock suckers emerging below the graft union, as these will be Prunus avium growth, not the cultivar.

Pruning Schedule

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Maintenance Level

moderate

⚠️ Toxicity Warning

Toxic to pets and humans