7 Japanese Blueberry Tree Problems and Solutions

The Japanese blueberry tree is an understory tree that is grown for its luxury, it is native to Japan and China but is now grown in many countries of the world like the United States, Canada, etc.

It is resistant to diseases and cost-effective in that it cost less in maintenance. This article discusses common Japanese blueberry tree problems, solutions when you observe problems and how to keep your tree healthy.

About Japanese Blueberry Trees

The Japanese Blueberry Tree also called the Green Emerald Blueberry, is a huge, broad-leaved member of the Elaeocarpaceae family that is indigenous to the temperate region of East Asia.

It is an evergreen tree, upright-growing, and used in gardens as an exotic or ornamental tree. It may grow to a height of 20 to 35 feet and is commonly found in evergreen forests between 1,300 and 8,000 feet of elevation which is across most of China and Vietnam.

Japanese Blueberry Tree

This popular hedging and topiary tree is loved not just for its fruit but because it is an ornamental exotic tree that offers year-round color and intrigue.

The dense evergreen foliage contributes to its beautiful charm. Springtime sees the emergence of bronze-colored leaves, which gradually turn a rich, lustrous dark green.

The Japanese blueberry fruits aren’t edible to humans but are fed by birds and animals.

Japanese Blueberry Tree Problems

The Japanese blueberry tree is disease resistant tree but these problems most possibly arise;

  • Sunburn
  • Chlorosis – Iron Deficiency
  • Sooty Tree Mold
  • Thinning Tree Canopy
  • Lack of Nutrients
  • Leaf Rust
  • Pest Invasion

1. Sunburn

Japanese blueberry tree problems

Japanese blueberry trees are vulnerable to sunburn because of their thin bark, the leave on top begins to die. Sunburned tree tissue will eventually die and stop feeding the leaves and branches above it with nutrition.

The brown bark on the side that receives the most sun will be your first indication of sunburn. This occurs as a result of the canopy you provided not sufficiently shading the tree’s top

Look at the tree trunk directly below the withering region to see where the harm has been done.

Sunburned leaves would wilt and turn yellowish brown and fall off.

The best solution to this sunburn problem is generally to prune the dead branches during winter and to cover the tree with a burlap sack to provide shade until new growth sprouts.

Including, protecting the tree from additional harm by covering it with a burlap sack or something comparable.

2. Chlorosis – Iron Deficiency

Japanese blueberry tree problems

Japanese blueberry trees are vulnerable to Chlorosis, an ailment typically brought on by a deficiency of iron. This condition is however easy to identify because Leaves become lighter in color or turn yellow. The increased dropping of  mature and premature, twigs and branch dieback may happen in extreme situations

The Japanese blueberry trees look best in neutral to slightly alkaline soils that are well-drained and fertile. In extremely high soil pH which rises beyond 6.5 or soil with poor drain structure, the tree is prone to developing chlorosis.

Chlorosis is caused by a lack of iron in the soil, which is a product of the soil’s high pH. Which makes it difficult for the tree to absorb iron in such soil.

By incorporating organic materials, such as leaf mold, animal dung, or compost into the soil, soil drainage can be enhanced.

Using Iron-containing foliar sprays would be beneficial for preserving the tree’s green hue and would show results improve in a couple of days

3. Sooty Tree Mold

A fungus called sooty mold, which appears as black silt or soot, can grow on any portion of a Japanese blueberry plant when honeydew a sticky, sweet material secreted by insect pests like aphids and whiteflies stays on your Japanese blueberry plant

One can easily scrape off the mold with your finger because it is typically not harmful to the overall health of your plant.

Mild sooty mold infestations could go unnoticed, but serious infestations are easy to spot because of the sooty mold’s accumulation on the foliage with a dark, shadowy appearance.

Two insects that signify the potential of sooty growth on your blueberry Japanese tree are the Yellow jackets and bees because these insects are drawn to honeydew.

Sooty growth gives the Japanese blueberry plant an ugly look, although harmless to the plant, the presence of large quantities of sooty growth could hinder photosynthesis as the leaves are covered with them, this would therefore cause the leaves to turn yellow and die.

Spraying the tree with water would easily wash off the presence of the sooty mold off the leaves temporarily.

Eradicating the presence of insects by the use of proper and controlled measures of pesticides would also preserve the Japanese tree.

Also, the use of Neem oil would prevent the resurfacing of the sooty mold

4. Thinning Tree Canopy

Regions of the Japanese blueberry tree that are not receiving enough sunlight, will suffer thinning of its canopy, This is frequently the case when they are planted beside a fence.

Your blueberry tree may be too close to other trees or Japanese blueberry trees if it receives adequate sunlight and water but still loses a lot of leaves. The tree may not be receiving enough nutrients to support the leaves if its roots are fighting for resources.

There are a few possibilities as to why your tree’s canopy may be reduced. The lack of water for your tree could be the first factor. Be extra careful to water your blueberry tree frequently if you live in a desert or a region with extreme temperatures.

Insufficient watering will cause your tree’s leaves to become sparser and expose the inner canopy to the sun. Japanese blueberry trees can burn in the sun, as I previously mentioned. If you want to grow this sort of tree in a hot, dry area, you must take extra care to water the tree sufficiently so it doesn’t get burnt.

5. Lack of Nutrients

Japanese blueberry tree

Every two to three years, the Japanese blueberry tree regularly loses its leaves. Fresh leaves will soon take their place after this happens. Under normal circumstances, the tree already loses a lot of leaves and fruit. Nevertheless, if the shedding intensifies, there can be a problem.

If your tree is losing leaves at an excessive rate, it may have leaf rust. To confirm if this is the case look at the color of the recently fallen leaves. If that’s not the case. Then your tree is most likely lacking in nutrients or sufficient soil drainage in this situation.

If you notice standing water around your tree or hard, compacted soil, you most likely have poor soil drainage.

To solve the problem of poor soil drainage, you need to start by adding compost to the soil around your tree.

This facilitates drainage. More air gaps will be created, allowing water to drain through. Add three to four inches of compost each year to significantly enhance drainage.

Use fertilizer in the spring, summer, and fall to keep healthy leaves growing and your tree nourished. It will have the best environment to grow tall and full thanks to this.

6. Leaf Rust


Leaf Rust is a Fungus infestation caused by Naohidemyces vaccinii, Yellow spots on the top and bottom surfaces of the normally green leaves are the disease’s initial signs. If the spots are untreated, they will eventually turn brownish-red, signaling the disease’s progression.

As soon as 10 days just after infection, signs of this disease would start to appear. Acute infections can cause entire leaves to fall, turn brown, or even die.

Warmer temperatures and prolonged rain are favorable conditions for this fungus to grow and spread infection and disease.

The condition can spread quickly on your tree. After 48 hours of moisture coming on the leaf, the fungus might begin to grow on the leaves. Hence it is advisable to water your Japanese blueberry tree only at the soil line, avoiding getting the Leaves wet and avoid overwatering.

To stop the spread, spray the tree with a licensed systemic fungicide, Bonide 811 Copper 4E would get the job done. Because fungicide application rates vary, read the label carefully. To prevent the disease from affecting a healthy Japanese blueberry tree, apply it in the early spring.

If the leaf rust is not correctly treated, it can also restrict growth and harm your tree in the future.

Gather any leaves that have fallen under the tree and burn them or put them in the trash. By doing this, the fungus won’t be spread by air, water, people, pets, or animals.

However, the Japanese blueberry tree is resistant to this disease so it would survive it but it would ruin the tree’s beauty and stunt new bloom.

To prevent any more leaves from becoming afflicted, I advise applying Bonide 811 Copper 4E Fungicide to the leaves.

Gather any leaves that have fallen under the tree and burn them or put them in the trash. By doing this, the fungus won’t be spread by air, water, people, pets, and animals.

In the winter season, some of the infected leaves will develop telia; this is a fungus structure that enables the fungus to survive the harsh climatic condition and go on to re-infect the Japanese blueberry tree in the spring.

7. Pest Invasion

Tree Borer

Another reason why the crowns of your blueberry tree are bare is a borer infestation. Borer species of insects consume the inner layers of the wood by tunneling into tree trunks.

They are often beetle or caterpillar larvae. If they had drilled through the trunk of your Japanese blueberry tree, they might have caused damage that prevented water from getting to the top of the tree, thereby causing that prevented water from getting to the top of the tree, thereby causing that stem and branches attached to it to wither and die.

Using pesticide sprays on your blueberry tree once or twice a year would preserve your tree from getting infested with these bugs.

Japanese Blueberry Tree Pros and Cons

The Japanese blueberry tree is a fascinating tree to have in your garden, these are its pros and cons;

Add New
It has evergreen glossy leaves
Excess water is harmful to it as it makes it prone to infection e.g sooty molds
It is resistant to diseases
It is prone to sooty mold fungus attack
It thrives in different climatic condition
Its leaves are not Deer resistant
It does need so much water to grow well
It can’t survive in compacted soils
It can thrive in alkaline to neutral soil
It can't thrive in Acidic soil
It does best in well-aerated soil vulnerable
Vulnerable to Chlorosis
It can absorb nutrients from the air, and it doesn’t need many supply
Warmer temperatures and excess rainfall is unfavorable to the Japanese blueberry tree
It is drought tolerant
The Japanese blueberry fruits aren’t edible for humans
It can be used as a shade-providing tree in private lounge separation because of its dense leave
Japanese blueberry trees has a thin bark
It has limited cold tolerance and won’t survive temperatures lower than -10 degrees Celsius
Extended exposure to hot sunshine is dangerous to the trees health
It can be pruned and shaped into luxurious styles to fit your garden desire
It has multiple heads rather than its single head when younger, hence it could occupy more space and be busy
It can grow in multiple climate conditions
Add New


The Japanese blueberry tree can give your garden the beauty you desire and a relaxing atmosphere. Make sure you give it the best conditions for growth, fertile aerated and well-draining soil, full sunlight and air circulation would allow your tree to flourish.

In situations where you can’t deduce what could be wrong with your tree call the nearest arborists (this is a profession that takes care of trees).

6 Japanese Blueberry Tree – FAQs

Which fertilizer is best for Japanese blueberry trees?

The best fertilizer for the Japanese blueberry tree is the Palm fertilizer, Use a high-quality palm fertilizer to fertilize in March, June, and October.


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