From beautiful flowers to breathtaking landscapes, plants with green leaves can bring beauty to the world and brighten your day. But sometimes, despite your hard work to maintain and care for green plants, they turn yellow instead.
Your leaves turning yellow is a cry for help. There are several reasons your plant might turn yellow. Here is everything you need to know below.
Why Plant Leaves Turn Yellow
Yellowing leaves are one of the first signs a distressed plant shows. Yellow leaves in green plants can be a symptom of any plant problem, some being not so serious and others being fatal if ignored.
Green leaves turn yellow because of a loss of chlorophyll, which is known as chlorosis If your plant’s leaves turn yellow during its final weeks of flowering, it is natural you have nothing to worry about. The plant is simply channeling resources to bud growth and allowing the leaves to die off. It is perfectly natural and is known as Senescence. Senescence refers to the natural yellowing and dying off of plants.
However, if the yellowing happens during the early weeks of flowering, or during vegging, it is most definitely something serious. Several problems could cause it. You are to find out what the problem is to fix it.
Causes of And Treatment for Yellowing Leaves
When your plant’s leaves turn yellow, how early you can discover the cause, will determine if you can save the plant. There are various reasons your plant’s leaves might turn yellow. Here are some of them below:
- Moisture stress
The most common cause of yellowing leaves is moisture stress. It could be from over-watering or under-watering the plant. If your plant’s leaves turn yellow, check the soil if it is dry or too wet.
Plants need water to survive and keep growing. However, too much water can cause the plant to rot. When plants look pale or sick, most people react by watering. But several times, more water is not the solution. Plant roots cannot breathe and access nutrients from the soil when they are soaked in water.
Over-watering can mean several things. It could mean you are putting in too much water at a time or putting in the right amount of water but too frequently. You also could have gotten everything right, but your plant’s pot does not have drainage holes, or the ground’s soil makeup is not known.
Key indicators: The symptoms of over-watered plants may not only be yellowing leaves; some symptoms might be like symptoms of nutrient deficiency, like swollen and droopy leaves.
Overwatered plants might also have their roots rise from the soil to avoid suffocation. And if you smell a nasty odor from the plant, the seeds are most likely rot.
Treatment: The treatment for over-watering is simply less watering.
However, you need to ensure that you have good drainage. You have a drainage issue if the water takes too long to drain out of the pot.
To know how often you should water your plant, stick your finger in the top of the soil. If it feels dry, then you need to water it. Furthermore, when you plant outdoors, do not plant in areas where water pools.
Under-watering is less common than over-watering and plants can better handle less water than an abundance of it.
This occurs most times when your pot is too big for the plant. The leaves asides from turning yellow may become thin and droopy.
Key indicators: Yellowing leaves, stunted growth, dry leaves, and parched soil.
Treatment: Watering the plant fixes the problem. Water the plant more often and add a layer of mulch in dry areas for outdoor plants.
2. Nutrient Deficiency
Yellowing leaves in plants can also be a symptom of Nutrient deficiency.
A lack of basic nutrients in plants can cause their leaves to turn yellow and wilt. Lack of such nutrients can cause stunted growth and prevent plants from carrying out their vital functions.
On the other hand, too many nutrients can cause a nutrient burn, which can also lead to yellowing leaves.
The pattern in which the yellowing occurs, tells you the kind of nutrient your plant lacks.
Lack of nutrients (Under-fertilization) causes green leaves to turn yellow and an abundance of nutrients (Over-fertilization) causes leaves to become vibrant yellow, crunchy, and curly.
Lack of Nutrients(Under-fertilization)
Another reason green leaves turn yellow is that the soil in which they are planted lacks essential nutrients. These plants show different symptoms.
Plants should absorb the essential minerals for their survival from the soil, and different plants require different nutrients to survive.
Deficiency Signs And Treatments for Essential Nutrients
Here are some of the signs of some nutrients deficiency and their treatment.
Signs: Yellowing leaves, distortion. In tomatoes, blossom-end rot.
Treatment: Test the soil’s acidity with lime, or its alkalinity with gypsum.
Signs: Yellowing begins at the center vein and moves outward as it progresses, causing stunted growth.
Treatment: Apply manure-based compost to the soil, or make use of coffee grounds.
Signs: Leaves become chlorotic; yellow with green veins, stunted growth.
Treatment: Test the soil pH level and lower it to under 7.
Signs: Leaves’ edges and tips turn yellow, and mature leaves develop brown spots or yellow-brown veins.
Treatment: Apply veggie and fruit-rich compost to the soil, or bury citrus rinds and apply it at the base of the plant. You could also consider using a potassium-specific fertilizer.
Signs: The leaves turn yellow with white stripes along still-green veins, appearing first on lower limbs.
Treatment: Apply compost manure or fertilizer rich in magnesium sulfate (Epsom salts) to the soil.
Signs: In-between large veins, the leaves appear lighter and discolored.
Treatment: Apply a fertilizer containing zinc, or spray with kelp extrac.
An abundance of Nutrients (Over-fertilization)
Lack of nutrients causes your plants not to perform well, however they can also be overfed too. Too much fertilizer stunts plants’ growth, disrupts the underground ecosystem, causes the plant to have difficulties absorbing nutrients, and prevents plants from blooming. It can also cause the leaves of the plant to yellow.
Signs of Over-fertilization: Yellow or brown leaves, wilting leaves, root rot, tainted growth, leaf drop, fertilizer crust on the soil’s surface.
And in nitrogen, an abundance of tree branches and leaves with much or no fruits.
Treatment: Get rid of visible fertilizer on the soil’s surface and remove all dead leaves and plant residues. Water the plant deeply and wait up to a month before fertilizing the soil again.
Light burn can also cause yellowing leaves, and conversely, not enough light can cause the yellowing of leaves.
Too Much Light
Indoor plants are grown under artificial light (grow light) must be placed in the perfect position, not too far from plants and not too close to the plants to prevent the grow light from burning the leaves and causing them to turn yellow.
The leaves will turn yellow and brown from the intense heat when the light is placed too close.
Treatment: Hang your grow lights according to the manufacturer’s instructions. Follow each guideline to position the light properly.
If the light is too close, hang it higher, or you can dim the lights if you have dimming grow lights.
Too Little Light
Plant leaves can also turn yellow if they do not receive enough light. Plants cannot photosynthesize when there isn’t enough light. Photosynthesis is therefore limited due to low light. When the light is increased, photosynthesis can take place. Yellow leaves are common in house plants because of how much light the plant receives.
Treatment: Moving your plant to a sunnier location is the only way to help the situation.
Note: If yellowing leaves occur in your plant during flowering, insufficient light is not the issue.
The temperature can also cause a change in the coloring of leaves when it’s too hot and when it is too cold.
Some plants are susceptible to changes in temperature. For instance, tropical plants, like orange trees, do not fare well in drafty locations. Placing a temperature-sensitive plant beside a door or a vent can cause its green leave to change color and even cause leaves to drop.
Windowsills can provide the best source of light for plants. However, they can also be terrible for regulating temperature, especially if your windows are really old and poorly insulated.
Signs: Yellowing leaves and leaf drops.
Treatment: Place the plant in a warmer location. A few days out under the sunlight will revive the plant and chlorophyll will return to the leaves.
5. Root Rot
Root rot can also cause yellowing leaves. Root rot is a microbial condition for bacteria that attacks the root system of plants.
When the root becomes too damp from too much moisture and over-watering, it becomes a breeding ground for fungi, bacteria, and algae. These organisms then attack the roots in these conditions and cause them to rot.
This results in the yellowing of leaves, brown and slimy roots, leaf drops, and a droopy and withered look.
The yellow leaves are most likely the first sign you’ll see. They change color quickly and fall out easily. Once your plant has been infected, there isn’t much to do. So you have to do your best to prevent it.
Treatment: Transplant the infected plant into fabric pots to boost drainage and increase aeration.
Although they are difficult to see with the naked eye, mealybugs, spider mites, and beet leafhoppers may destroy your plant.
Some other pests can attack plants.
If you have studied and ruled out all other potential causes of yellowing leaves, a pest infestation might be the problem.
Signs: The damage done to your plant and the symptoms shown by your plants will differ depending on the type of pest. However, yellowing leaves are a common sign for most.
When you notice the change, find and identify the pest causing all the trouble. Inspect your leaves carefully.
Treatment: There are several treatment options, both chemical and organic.
However, regular cleaning of plants with insecticidal or horticultural soap is safe and effective.