Guava is a wonderful tropical fruit that has a sweet flavor. It is rich in vitamins, minerals, and fiber. Also, the guava plant can grow under a wide range of environmental parameters. Thus, most people tend to grow it in their gardens and backyard. On the other hand, guava trees need little maintenance. Hence, it is easy to keep this lovely fruit.
The leaf’s color of the guava tree ranges from light green to dark green. But some people experience guava tree leaves browning. Also, they are worried about the survival of the plant. As an agriculturist, I’ve also inspected these symptoms. So, here I mentioned the primary reasons that cause to turn guava leaves brown.
If your guava leaves turn brown unusually, your plant may infect any disease or suffer from a lack of nutrients and unfavorable environmental conditions.
Let’s dive deep!
Anthracnose disease
This is the most common fungal disease that affects plants, including guava. However, if you identify the symptoms earlier, you can control them. Because the late stages are difficult to control.
Do your guava tree or plant show the below symptoms?
- Young shoots die back dramatically while fruit and leaves are still attached
- Fruit and leaves develop small black dots that quickly grow into a dark brown
- Sunken lesions on the guava leaves, tip, or margin
- cankers on twigs and stems
- Immature leaves, fruits, young shoots fallings
Normally this disease often starts from guava leaves and twigs of trees. So, if you notice all of the above symptoms or one of them, your guava plant is probably affected by Anthracnose disease.
Like other fungal diseases, Anthracnose disease can also survive on dead tissues. Also, they may spread out rain splashing. Therefore, you should apply treatments immediately for affected guava plants and leaves.
Treatments of Anthracnose disease
You can apply fungicides that work against Anthracnose fungal disease. But these chemicals protect only the healthy tissues. They do not eradicate existing infections.
Here, you can use the bellowing types.
- Fungicides that contact copper
- Propiconazole (e.g., Banner Maxx II)
- Di-ammonia diacetate(e.g., Liquicop)
- Thiophanate-methyl (e.g., Cleary’s 3336)
Always read and follow the label direction and doses when applying the chemicals. Spraying fungicides is the most common method.
Management practices of Anthracnose disease
If the case is not severe, you can control the disease spreading by doing the following things. Management is better than treatments. Therefore, always try to do plantations with better practices.
Pruning
You are pruning and destroying the infected guava leaves, twigs, and branches. Here you can burn or bury them to prevent contact with other plants.
Also, you can choose the winter season to prune. It will help you increase air circulation in the canopy and remove the affected part of the plant.
Sanitation
Also, raking and disposing of guava leaves daily from the garden is essential. It will reduce the disease spread.
Use Guava plants varieties that resist anthracnose fungi
If you plan to grow a new guava plantation, use cultivates that resist anthracnose-causing fungi. The genetically modified varieties are available on the market.
Also, plant your guava plants with enough space. It facilitates maximum air circulation and increases sunlight exploration.
Algal leaf spots on guava leaves
Sometimes your guava leaves may get brownish during humid weather conditions, and it may be a parasitic algal infection because a humid environment provides ideal spaces to go algae.
If you notice brown spots on your guava leaves, most probably, they may be infected with this disease. However, it is relatively harmless.
But at the severe stage, it can reduce vigor and decrease the plant’s energy. Also, the black sunken spots may appear when parasitic algal infections severely affect the guava plant.
You can protect your guava plant from this disease by doing simple things. Use the below tips.
Treatment
- Decrease the humidity around your guava plant
- Pruning it and nearby plants to allow better airflow to all parts of the canopy
Stressful environment
As I mentioned above guava tree is a tropical and sub-tropical plant. Thus they prefer bit good drainage and full sun.
So, guava trees are unable to tolerate temperatures below freezing. If they face that type of situation, the leaves may get yellowish or brownish. Commonly, this happens in the spring season.
If you see these symptoms in the winter season, you can take the guava plant onto the indoor. Or else, wait until warmer weather come back!
Lack of nutrients or water
Nutrients are the key components that control the plant’s health, crop, and growth. So, if your guava plant is suffering from nutrient deficiency, it may show by plants’ leaves, crops, and diseases.
Therefore, to get rid of these situations, add guava tree fertilizer with 6-6-6-2 (Nitrogen: Potassium: Phosphorous: Magnesium) ratio. Also, do not try to over fertilized them. It also causes to turn guava leaves brown.
Also, if you notice your guava leaves turn brown and fall into the ground, check its surroundings. Sometimes your plant does not have a good water supply.
Water is a vital factor for every living thing. Lack of water can dehydrate the plant. Then these leaves are get dried and fell. So, properly add water to the guava plant at dry seasons and at the immature stages.
Nematodes attract on guava leaves
The guava plants may be attracted by nematodes, especially on guava roots. Then, the guava tree’s water and nutrient supply will block or reduce.
As a result of that, the tree healthiness will reduce and more susceptible to diseases. Therefore, these types of trees can easily be infected by other diseases such as Anthracnose.
In the beginning, the lack of water and nutrients also caused the guava plant to shrink the leaves. Then these dried leaves can get yellowish and turn into a brown color.
Finally, these dead leaves fall into the ground. Add Carbofuran 10g to control the nematodes on guava effectively.
