scienceExpert DiagnosisUpdated Feb 20, 2026

Cherry Blossom Leaf Spot

A fungal leaf spot disease of cherry and flowering cherry trees caused by Botryosphaeria obtusa. Presents as small purple-brown spots on leaves that develop tan centers and yellow halos, often leading to premature defoliation in cool, wet springs and repeated seasonal infections if inoculum is not reduced.

Cherry Blossom Tree showing leaf spot symptoms

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Quick Diagnosis

Most Likely Cause: Cherry leaf spot (Botryosphaeria obtusa).

Small purple to brown circular spots with tan or gray centers and yellow halos on leaves in spring and early summer; spots coalesce, cause early leaf drop, and can be accompanied by twig lesions and occasional dieback on susceptible cultivars, so plan winter pruning to remove infected wood and speed recovery using winter pruning techniques.

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Cherry leaf spot is a common fungal disease of ornamental and fruiting cherries, including many flowering cherry cultivars. It rarely kills a healthy mature tree outright, but repeated severe defoliation reduces vigor, stresses trees, and harms spring bloom and fall appearance.

The pathogen overwinters in infected leaves and twigs. In spring, cool, wet conditions and prolonged leaf wetness favor primary infections, and then repeating rain events produce secondary infections throughout the growing season.

Growers should prioritize sanitation, targeted pruning, and fungicide protection for high-value or highly susceptible trees during wet springs. Managing inoculum and microclimate gives the biggest long-term payoff.

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Plant Problem — See AlsoCherry Blossom Poor Flowering

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How the disease progresses and how to tell it apart

Primary infections usually start at bud break when spores from last season's infected leaves and twigs are splashed to new foliage. New spots appear within days in cool, wet weather and often carry a purplish margin with a tan or gray center. Secondary cycles follow during rainy periods, quickly increasing the number of spots and causing leaves to yellow and drop.

Twig lesions and small cankers may appear later if infections move into shoots. Repeated yearly defoliation weakens the tree and can lead to twig dieback or reduced flowering the following year; this is more common on susceptible cultivars and young trees.

Differentiating from powdery mildew: powdery mildew forms white, powdery patches on leaf surfaces rather than discrete purple-centered spots, and it prefers warm, humid conditions with less free water on leaves. Differentiating from fire blight: fire blight causes blackened, wilted shoots and a shepherd's crook on new growth, often with bacterial ooze on infected tissue-symptoms that are distinct from spot-driven defoliation caused by Botryosphaeria obtusa.

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Environmental Baseline

Before diagnosing specific failures, confirm your Cherry Blossom Tree's environment matches its core care requirements.

forestCherry Blossom Tree Care Needs

Light: Full sun (6+ hours)
Water: Moderate, consistent moisture first 3 years
Temp: Cold hardy to about -20°F once established

homeTypical Indoor Home

Humidity: 30-50% (Low)
Temp: 65-72°F variable
Light: Often too dim or direct

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Possible Causes

Sorted by likelihood

1. Botryosphaeria obtusa (fungal pathogen)

Likelihood: High

A fungal pathogen that produces spores on infected leaves and twig lesions; spores are splashed by rain to young leaves in spring, causing primary infections that seed later infections.

Identification

remove_circle_outlineSpring spotting on newly emerged leaves with purple-brown margins and tan centers
remove_circle_outlineYellow halos surrounding lesions on the upper leaf surface
remove_circle_outlineBlack specks or small fruiting bodies may be visible on older lesions
remove_circle_outlineLook for twig lesions or cankers later in the season on heavily infected branches

The Fix

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Root Health Examination

A direct inspection of the root system distinguishes root rot from drought stress — saving weeks of guesswork.

check_circleHealthy Roots

Firm to the touch
White or light tan color
Earthy, pleasant smell

cancelCompromised Roots

Mushy or slimy texture
Dark brown or black color
Sour, rotting odor

Inspection Step: Gently slide the pot off while supporting the base of the stems. The outer root ball gives sufficient clues without disturbing all the soil.

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When to Worry

A few yellow leaves are normal. If more than 20% of foliage turns yellow within a week, or new growth is affected, act immediately — check the roots first.

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Recovery Protocols

Recovery takes time. Once the root cause is corrected, implement a 30-day stabilization window.

Immediate (0-4 weeks)Stop the spread this season

Rake and remove infected fallen leaves now, prune out twig lesions during dry weather, and switch to drip or targeted watering to reduce leaf wetness. If spring rains are ongoing and the tree is high value or heavily infected, begin protectant fungicide sprays at bud break and repeat on the label schedule during wet periods.

Short term (4-12 weeks)Support recovery and monitor

Expect reduced foliage and some yellowing for several weeks after heavy infections. Keep trees mulched (not piled against trunks), water deeply during dry spells, and hold off heavy pruning until late winter. Fungicide treatments now protect new leaves during continued wet weather but will not reverse existing lesions.

Medium term (3-9 months)Fall cleanup and winter prep

In fall, remove and destroy leaf litter and any dropped infected fruit or debris to reduce overwintering inoculum. Plan winter pruning to remove cankers and thin the crown, which reduces spore production the next spring.

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Preventing Future Issues

Prevent recurrence by combining seasonal sanitation, canopy thinning, and timely protectant fungicide applications in wet springs; when planting, prefer less susceptible cultivars and avoid sites with prolonged leaf wetness for long-term disease reduction, and handle leaf litter carefully with proper leaf disposal to lower the local spore load. To confirm Cherry Blossom Leaf Spot, correlate symptoms with a cool, wet spring and the presence of leaf spots on multiple leaves. If only a few spots appear, monitor for spread before treating.

Cherry Blossom Leaf Spot

Quick Diagnosis

How the disease progresses and how to tell it apart

Environmental Baseline

forestCherry Blossom Tree Care Needs

homeTypical Indoor Home

Possible Causes

1. Botryosphaeria obtusa (fungal pathogen)

Identification

The Fix

Root Health Examination

check_circleHealthy Roots

cancelCompromised Roots

When to Worry

Recovery Protocols

Preventing Future Issues

2. Cool, wet spring weather and prolonged leaf wetness

Identification

The Fix

3. Highly susceptible cherry cultivars and young trees

Identification

The Fix

Cherry Blossom Leaf Spot

Quick Diagnosis

How the disease progresses and how to tell it apart

Environmental Baseline

forestCherry Blossom Tree Care Needs

homeTypical Indoor Home

Possible Causes

1. Botryosphaeria obtusa (fungal pathogen)

Identification

The Fix

Root Health Examination

check_circleHealthy Roots

cancelCompromised Roots

When to Worry

Recovery Protocols

Preventing Future Issues

Related Reads

2. Cool, wet spring weather and prolonged leaf wetness

Identification

The Fix

3. Highly susceptible cherry cultivars and young trees

Identification

The Fix