When you see evergreen shrubs turning brown, they face different stresses like poor soil, incorrect lighting, insufficient water, mineral deficiency, and fungus attack.
Don’t worry; it is really easy to stop discoloration. Stay till the end to know about every stress and how to deal with it easily.
JUMP TO TOPIC
- What Are the Causes Behind Evergreen Shrubs Turning Brown?
- How Do You Save Brown Evergreen Shrubs?
What Are the Causes Behind Evergreen Shrubs Turning Brown?
The causes behind evergreen shrubs turning brown are generally when they face soil problems and heat stress. In addition, nutrient deficiency, unavailability of water, and some environmental factors can also cause discoloration. Shrubs become brown in the autumn season too, which is natural.
– Nature’s Way
Sometimes, evergreen shrubs turn brown, and it’s not anyone’s fault. It is common to see seasonal needles or leaves changing color to brown in the fall or autumn. You may see a needle drop from the shrub too.
However, it is natural, and the evergreen shrubs you are growing will fix themselves when the fall season ends.
– Soil Problems
If the season is not autumn, the shrubs face some stress. The leading one that causes browning is soil issues. If the soil is problematic, the effects will be visible on every part of the shrub.
A common soil problem is unsuitable pH. Evergreen shrubs or trees love slightly acidic soil, ranging from 5.5 to 6.5. However, the root performance will take a hit when it is basic, and you will see needles turning brown.
Poor drainage is another undesirable condition that causes a lot of issues. The biggest ones are waterlogging conditions and affecting root stretching. When you apply water, and the drainage properties are poor, the water will stay around the roots, which will cause overwatering problems.
In addition, roots cannot breathe properly as the oxygen supply gets limited. Similarly, such soil has big clumps, so roots will find it hard to grow and become stronger. Furthermore, soil can also be the home for insects. Many insects lay their eggs in the infested soil in large numbers. This ultimately causes insect infestation, which can cause shrubs to become brown.
– Too Much Sun
“Why is my evergreen turning brown in the summer” is a common question, and the answer is simple – heat stress. If the shrubs are exposed to too much sun, sunburn will occur. The needles will have brown marks as the cells start to die because of the light’s intensity.
When brown marks appear on them, photosynthesis will not take place as it should. This will cause a “food shortage” in the shrubs, making them brown. So, growing shrubs in different sunny areas is not a good idea.
– Drought Stress
Evergreen shrubs can only remain green if you apply water regularly. The reason is that water is super important for almost every function in them. So, when they face water stress, these functions will not happen. As a result, brown patches on shrubs will be visible.
In addition, shrub needles also get wrinkly when the soil is completely moisture-less. If the soil stays dry long, these needles can also start wilting. That is also how to tell if a shrub is dying. When the needles wilt, the only thing left is tree death.
– Insufficient Light
When you notice an evergreen tree turning brown from the bottom up, it is likely facing light stress. The needles of shrubs or trees need sufficient light to stay green. It is because the light is converted into chemical energy within the needles, which shrubs utilize to keep their shape and color.
Thuja is a popular evergreen shrub that needs more than six hours of light to maintain its true colors. Similarly, five to six hours of light is enough for juniper shrubs. Mountain laurel is another common shrub that loves partial shade. If these shrubs or any others get less light than they need, they will become brown with time.
– Cold Temperatures
You may also see an evergreen turning brown in winter. The reason is that the physiological processes (including photosynthesis and transpiration) can be affected when the temperature drops below the required.
Here’s an example. Shrubs like Rhododendrons and Holly cannot tolerate temperatures lower than 20 degrees Fahrenheit. When the temperature drops below this limit, the moisture in the shrubs will freeze. As a result, water deficiency will occur, stopping all the processes within them. Therefore, the shrubs will instantly discolor to brown.
– Nutrient Stress
Evergreen trees need nutrients to complete internal processes. These nutrients make up chlorophyll – a pigment that makes needles green.
So, chlorophyll production will slow down if you don’t apply fertilizers. This will cause discoloration, and the shrubs will start having brown patches.
– Fungus Attack
When you observe evergreens turning brown from inside out, fungus diseases have attacked them. Root rot is among the most common tree diseases that can cause discoloration. In this disease, the fungus attacks the roots and can even kill them if you don’t stop the spread.
When the roots get harmed, the uptake of water and minerals will be halted. When this happens, the shrubs will become fragile. The needles will also change their color to brown and can even droop too.
– Transplant Damage
Is your newly planted evergreen turning brown? It means they are facing transplant shock. It is a condition in which roots take some time to start absorbing water and nutrients because of the new environment. You should follow this guide on how to properly transplant shrubs!
During this time, the needles can lose their green color and become brown. So, how to revive dying shrubs?
How Do You Save Brown Evergreen Shrubs?
To save brown evergreen shrubs, ensure the soil is in good condition with proper pH and drainage capabilities. It is also advised to let plants enjoy adequate water and light. It would be best to protect yourself from environmental stresses to avoid discoloration.
– Improve Soil Conditions
When shrubs face stress, the first thing to do is check whether the soil is good for them. For this, you should have a gardening box or cabinet where you put every important tool designed for checking soils.
To measure soil pH, use pH strips or a pH meter. If it tells you the soil is alkaline, add sulfur to make it slightly acidic. You should also own a moisture meter. Use it to find out if there is any moisture in the soil.
This will help you in avoiding problems like overwatering or underwatering shrubs. You should also have a shovel to remove the upper soil layer and add a well-drained one.
If you still see more brown spots on evergreen shrubs, completely replace the soil. Doing this will get rid of insect eggs and pathogens. Moreover, uproot any weeds you see and keep the garden clean to avoid pathogen attacks.
– Water Properly
If you grow shrubs, you must follow proper watering practices. Apply it only when the soil gets dry. When you find out the soil is completely moisture-less, apply water immediately without wasting any second.
Furthermore, do not sprinkle water on the needles. This can cause fungal growth, which will lead to more discoloration. However, spraying water on the shrubs is a good option when there is heat stress.
– Add Fertilizers Adequately
To maintain needle color; you should apply fertilizers regularly during the growing season. Organic fertilizers like compost should be on your list as they are inexpensive and environmentally friendly.
– Provide Protection From Environmental Stressors
It is super important to grow evergreen shrubs in a well-lighted area where they can get around six hours of light. More or less of it can lead to browning. If shrubs are facing heat stress, then you should also do something to provide shade.
In case of winter stress, experts suggest bringing the shrubs indoors if they are outdoors. Moreover, heaters can also be used to maintain the temperature to the ideal range of 50 to 70 Fahrenheit. This will help evergreen shrubs maintain their natural colors.
Evergreen shrubs change their color to brown when they face different kinds of stress. Luckily, you can easily fix these problems by following specific measures.
Here are the main points about how to stop evergreens from turning brown:
- Ensure the soil has ideal pH levels of 5.5 to 6.5, excellent drainage properties, and is free of pathogens.
- Add water and fertilizers adequately to maintain shrubs’ colors.
- Let them receive direct light for six hours.
- To protect shrubs from heat stress, shade them. In case of cold stress, bring them inside and use heaters.
Follow these points carefully, and the evergreen shrubs will keep their natural colors without facing any issues. Find here the causes and solutions if black spots appear on your shrub’s leaves.