If trees with brown leaves is an issue in your garden, they likely face problems like sunburn, water stress, poor root system, insect infestation, and diseases.
The good thing is it is really easy to fix this problem – the first step being to shade your trees.
Continue reading to know the causes behind leaves becoming brown and how you can treat them. Let’s begin!
JUMP TO TOPIC
- What Causes Trees With Brown Leaves?
- What To Do When Tree Leaves Become Brown?
What Causes Trees With Brown Leaves?
The causes of trees with brown leaves are mainly because of environmental stress and bad growing practices. Environmental stress includes improper lighting, frost, and dry soil. Poor practices mean not adding adequate water, transplant shock, not taking care of roots properly, and doing things that promote bacterial and fungal diseases.
– Too Much or Too Little Light
One of the main reasons tree leaves become brown is if they are exposed to sunlight for a longer time. It happens because high-intensity light can cause moisture dryness and cell death (if it gets severe). But can leaf scorch kill a tree? Yes, if the situation persists.
High-intensity light mainly affects the young trees/leaves, which are soft and tender. So, when you see new tree leaves turning brown, know the reason is heat stress. After some time, the older leaves too will change their color from green to brown if you don’t do anything to provide shade or reduce the impact of heat.
Similarly, people also ask- Why do tree leaves turn brown in autumn? Well, it is because light gets dimmer in this season, which impacts photosynthesis. When this happens, plants produce less food/energy, leading to brown spots.
– Bone Dry Soil
Trees need adequate water for survival because roots take nutrients from the soil when it is moist. So, nutrient uptake will take a hit if the soil gets dry. As a result, trees will start having brown spots on their leaves.
Furthermore, water evaporates from the leaves when there is extreme heat to initiate a cooling effect. So, if you water trees frequently, there will be no vigor in the leaves. Therefore, they will start turning brown and eventually die.
– Adding More Water Than Required
Overly moist soils are not a good thing for trees. They thrive best in an adequate amount of water. It is because when you over-moist the soil, roots face difficulty in breathing. Yes, roots also need oxygen to carry out their functions properly. But if they stay submerged in water, their oxygen supply will get restricted. If it happens, prepare to face the “leaves turning brown and crispy” situation.
Furthermore, extra moist soil can provide a favorable environment for root rot. In this disease, tree roots start to “rot” and cannot take up water and nutrients. When this happens, there will then come a time when leaves will start to turn from green to brown.
Frost is another reason which causes leaves to change their color to brown. In this condition, evaporation and photosynthesis goes dormant due to extremely low temperatures. So, all the physiological functions in leaves will stop, and they will start having big brown patches. After some time, the whole leaf will become brown and eventually fall off.
Those trees that are sensitive to extremely low temperatures face the most damage. For example, you will likely see oak tree leaves turning brown during frost. You might also see magnolia tree brown leaves if you are growing it.
Similarly, get ready to see some oleander brown leaves when the temperature dips. These are some of the brown tree names that are highly sensitive to frost. Almost every summer-loving tree hates the winter temperature, so don’t try to grow them if you live in such an area where frost or snow falls a lot.
– Transplant Shock
When you have recently transplanted a tree, and its leaves start having brown patches, the higher chances are that transplant shock is the reason behind it. It happens because roots need time to adapt to the new environment and grow properly. Trees might show leaf discoloration and poor growth until they do.
– Weak Root System
When tree roots face any unfavorable condition or get damaged, leaves becoming brown is inevitable. A poor or weaker root system must absorb nutrients and water more efficiently. So, trees will start facing water and nutrient deficiency, and the impact will be visible in the leaves.
Root problems occur for several reasons like poor transplanting techniques, bad soil conditions, improper watering, and much more. Furthermore, if trees are young, then they are more prone to face root complications.
Bacteria and fungi may develop on trees because of the animal dump they excrete near them. It is not a good thing as their attack can cause wilting and discoloration problems in the leaves of trees, which become brown.
So, which tree diseases are common? Bacterial leaf scorch, leaf spot, and Fire Blight are three harmful bacterial diseases that trees face. Similarly, rust, powdery mildew, anthracnose, and root rot are common fungi diseases that turn the leaves brown.
– Insect Infestation
Pests suck sap from the leaves, which causes brown spots on the leaves. When their population goes out of control, and you see them everywhere, then immediately start some treatment. It is because when hundreds of insects feed on a tree leaf, the whole of it can get brown and eventually die.
Moreover, pests can damage the tree’s stems, roots, and shoots, affecting its growth and health. Some of the common tree insects are aphids, spider mites, scale insects, gypsy moth caterpillars, leaf miners, bagworms, etc.
What To Do When Tree Leaves Become Brown?
When leaves become brown you should protect trees from excessive sunlight, add water properly and with care, apply organic or chemical insecticides, and use bactericides or fungicides to cure diseases. You must also keep observing leaf behavior frequently to detect any problem at an early stage.
– Shade Trees To Protect From Light
Trees need proper sunlight to continue the process of photosynthesis. Both low light and overexposure to light can cause problems. Therefore, you must first select a spot to grow trees where adequate light falls.
But if you have already grown them in those locations exposed to high light intensity, follow some tree care tips to avoid leaf scorching. You can use a shade screen or reflector to reduce the intensity. You can also apply cheesecloth on the tree branches, which will act as a protective layer. Doing these things will protect trees from sunburn to a great extent.
– Add Water Properly
Water availability for roots is super important if you don’t want poor flowers with brown leaves or any other complications. The young trees need daily watering to develop their roots and grow.
For older ones, you should apply water to a depth of 18-24 inches after every two weeks or according to the weather conditions of your locality. You might have to apply more in summer, and in winter, you might skip irrigation. It all depends on the presence of soil moisture.
To know about moisture status, try to insert an index finger in the soil. If you sense the soil is already moist, wait for it to dry, as overwatering can cause problems too. If it is dry, you should immediately apply water and a layer of mulch for moisture conservation. You can also use a moisture meter to read the moisture presence accurately.
– Apply Insecticides
Apply neem oil spray when you spot insects around and on the trees. You can also go for insecticidal soap as it is cheap and environmentally-friendly. Try chemical pesticides if you still see more insects after using these organic repellents. These are expensive and a little controversial, but they always work.
– Deal With Diseases
In bacterial or fungal diseases, apply bactericide or fungicide according to the disease. In addition, you should also prune off the extra parts so that it improves air passage. When aeration gets better, the chances of diseases go low.
Also, apply water in an adequate amount to prevent fungal attacks. Similarly, you must cut off the infected parts and bury or throw them far away. These tree care tips will prevent disease spread and help trees stay healthy.
In the end, it is crucial to keep trees from having brown leaves. Now, you know all the reasons and proven solutions to deal with this problem.
Check out these main points of the article to revise everything:
- Ensure trees receive sufficient sunlight, or the leaves will become brown.
- Add an appropriate amount of water for better leaf vigor and health.
- If you spot insects, apply organic insecticides like neem oil spray first. In the worst case, go for chemical insecticides.
- To prevent disease attacks, improve aeration and water practices. If trees still get affected, use appropriate bactericides and fungicides.
That’s all about the reasons tree leaves become brown and what you can do to fix them.