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Why Plant Leaves Turn Yellow

Gardening needs peer knowledge and interest. One mistake could make your plant die. However, we explore fresh things while doing gardening.

From growing a plant to its harvesting needs vital care, say watering, nutrition application, pruning if needed, weeding. All of these should be done at the proper time. The major problem that gardeners face while gardening is the illness in the plant. And the most prominent one is the yellowing of the leaves of the plant. Today in this blog I will write about the different types of yellowing of leaves and how to cure that.

Yellowing of leaves can occur due to various reasons say overwatering or underwatering, excess nutrition application or nutrient deficiency. Many times, it may occur due to improper soil pH and root damage or compacted roots. I will today discuss all of the above scenarios.

Why Plant Leaves Turn Yellow
Overwatering or Underwatering:

Improper watering or poor drainage is the major reason behind the yellowing of leaves. In waterlogged soils, roots can’t able to deliver water and nutrients to the plant due to the occurrence of anaerobic conditions in the soil. On the contrary, due to a lack of moisture, the plant can’t capable to take up essential nutrients from the soil.  To fix this issue avoid overwatering of plants. 

You must follow the general rule of watering the plants i.e. finger test. For this, put your finger a few inches deep into the soil. If the soil feels dry then water the plant thoroughly. Wait for a few days if the soil is watery. Your pot must have a drainage hole underneath for the removal of excess water and proper aeration.

Root Damage or Compacted Roots

It happens due to a number of reasons such as root rot, disease attack, injury by farm implements, small-sized pots etc.  In these cases, roots are not able to deliver proper water and nutrients to the plant. Due to the unfunctionality of roots, plants show their symptoms through the yellowing of leaves. It might be happening due to the compaction of roots in a congested area of the pot. 

A compacted area inhibits the movement of water, oxygen and nutrients to the plant. For this, first, you can prune the unhealthy roots and then repot your plant in a big container. Thumb rule for healthy roots i.e. plant with white-yellowish roots is healthy. Dark rotting roots with a foul smell indicate unhealthy roots.

Unbalanced soil pH

 Most plants grow well within a pH range of 6.0 to 7.0 i.e. neutral to slightly acidic. Fluctuation in the plant’s optimal range of pH leads to less availability of nutrients to the plant. Although soil is rich with nutrients however roots are not able to deliver nutrients upward. So, you should maintain the pH balance of the soil.

Deficiency or Oversupply of nutrients: – For their proper growth and development plants needs food. They need nutrients in the right proportion, not in lack or excess quantity. Plants need essential nutrients to complete their life cycle. Deficiency of any nutrient results in the yellowing of leaves. You need to identify how the yellowing starts and which leaves turn yellow first. I will give you some clues regarding excess or deficit of nutrients:

Nitrogen: – It indicates the general yellowing of older leaves. Further, it progresses toward the younger leaves. Surplus of nitrogen application causes necrotic lesions on leaves with reduced plant growth. It enhances the vegetative growth instead of the reproductive growth of the plant.

Phosphorus: – Inadequate supply of phosphorus causes stunted growth of plants with a purplish coloration of older leaves. Delay in fruit and seed settings is common. Oversupply of phosphorus leads to iron and zinc-deficient plants.

Potassium: – Insufficient potassium slows down the growth of the plant. Leaf margins turn bright yellow to brown in color. An overabundance of potassium results in Calcium, Magnesium and Nitrogen deficiencies. 

Calcium: – Uneven patches of yellow and green color are observed on tender leaves. Browning starts from the leaf tips. Gradually the growth of stem and roots ceases. Plenty of calcium causes Magnesium and Boron deficiencies.

Magnesium: – Interveinal chlorosis is generally seen on older leaves due to a deficit of magnesium. Sometimes curling of leaf tips is also observed. A high quantity of magnesium in plants causes calcium deficiency.  

Sulphur: – New leaves show symptoms of the bountifulness of sulphur in plants. It gives uniform yellowish coloration all over the leaf.

Note: The dearth or surfeit of any nutrient is examined by the visual symptoms of plants. The accurate analysis of the deficient nutrient is crucial to managing the problem.  Proper fertilization with plant foods is essential to keep your plants free from yellowing.