Here are the most common nutrient deficiencies in plants and how to fix them. In this story, we will cover symptoms of plant nutrient deficiency and treatment using widely available fertilizers.
Plants need nutrients from soil, water, and air for healthy growth. The composition of the soil directly affects the health of the plant. Important soil nutrients include nitrogen, phosphorus, potassium, calcium, iron, manganese, and many others. If any element is missing, the plant gets sick and may even die.
But how do you know what element the plant is lacking? The answer is in the plant itself. Each vital nutrient deficiency has its symptoms, which can be detected through monitoring. If identified in a timely manner, these deficiencies can be treated and the affected plant can return to health.
Editor’s Note: The “Big Three” plant nutrients are nitrogen (N), phosphorus (P), and potassium (K). These “N-P-K” numbers are prominently printed on most plant fertilizer packages. For example, a fertilizer that is listed as 4-8-4 contains 4 percent nitrogen, 8 percent phosphorus, and 4 percent potassium.
Nitrogen Nutrient Deficiencies in Plants
Nitrogen is one of the most important elements for a plant. It is one of the “Big Three” plant nutrients. It helps to maintain the necessary water balance and also stimulates the growth and development of the plant. A lack of nitrogen in the soil occurs most often in early spring, due to low soil temperatures that prevent the formation of minerals. So, the question is how to identify and fix nitrogen deficiency in plants?
Nitrogen deficiency is manifested in thin and sluggish shoots, small leaves and inflorescences, and low branching. In general, the plant does not develop well. In addition, the lack of nitrogen can be indicated by a change in leaf color. In particular the color of the veins, both central and lateral.
With nitrogen starvation, the veins first turn yellow, and later turn yellow and the perianth leaf tissue. Also, the coloration of the veins and leaves may become reddish, brown or light green. The signs of nitrogen deficiency first appear on older leaves, eventually taking over the entire plant.
Nitrogen deficiency in a plant can be mitigated by the application of fertilizers containing nitrates. These include potassium nitrate, ammonium nitrate, and sodium nitrate. These also include ammonium phosphate, ammonium sulfate, and urea. A high nitrogen content is present in natural organic fertilizers.
This element is especially important during flowering and fruit formation. Signs of phosphorus deficiency are difficult to confuse with any other symptoms. The leaves and shoots turn bluish in color, and the leaf surface loses its glossiness. In especially neglected cases the coloring may even turn purple or bronze. Areas of dead tissue appear on lower leaves, then the leaf completely shrivels up and falls off. Young shoots continue to develop, but they look weakened.
Phosphorus deficiency is treated with phosphorus fertilizers: rock phosphate, potassium phosphate, superphosphate. A large amount of phosphorus is contained in poultry manure.
Potassium Nutrient Deficiencies in Plants
Potassium is one of the most important elements of plant mineral nutrition. Its role is enormous: maintaining water balance, increasing plant immunity, increasing resistance to stress, and much more.
A lack of potassium leads to leaf burn (deformation and drying of the leaf edges). Brown spots appear on the leaf plate, the veins appear as if pressed into the leaf. Symptoms first appear on older leaves.
Often the lack of potassium leads to active leaf loss during flowering. Stems and shoots droop, plant development is slowed: appearance of new buds, sprouts, and fruit stops.
To compensate for the lack of potassium, add fertilizers such as potassium chloride, potassium magnesia, potassium sulfate, and wood ash.
Calcium is important for proper functioning of plant cells, protein and carbohydrate metabolism. This deficiency primarily affects the root system. Signs of calcium deficiency appear first on young leaves and shoots: brown spotting, curvature, twisting. Later, both already formed and newly emerging shoots die off.
Lack of calcium leads to poor absorption of other minerals. Therefore, the plant may show signs of potassium, magnesium, or nitrogen deficiency.
Lime fertilizers such as chalk, dolomite limestone, dolomite flour, and slaked lime can help increase calcium levels in the soil.
Magnesium Nutrient Deficiencies in Plants
Another important plant nutrient is magnesium. This mineral is essential for proper photosynthesis. In addition, magnesium is involved in redox processes. When there is a lack of magnesium in the soil, chlorosis occurs on the leaves of the plant. But unlike the signs of iron chlorosis, the lower, older leaves are affected first. The color of the leaf plate between the veins changes to reddish or yellowish. Spots appear all over the leaf, indicating tissue death. The leaf curls and wrinkles on the edges.
To eliminate the lack of magnesium, fertilizers that contain a large amount of the necessary substance are used. These include dolomite flour, potassium magnesia, and magnesium sulfate. Wood ash and ash also do a good job of improving magnesium deficiency.
Sulfur levels in soils can change rapidly under the influence of various factors. Soil type and moisture, weather conditions, and the biological characteristics of crops all influence the sulfur availability of plants. Externally, sulfur deficiency is manifested by pale green and yellow coloring of young plant leaves. This chlorosis can resemble nitrogen deficiency symptoms. However, nitrogen deficiency first appears on older leaves.
A small need for sulfur can be corrected by foliar feeding with readily soluble forms of fertilizer. If sulfur deficiency is detected at an early stage of plant growth and is timely treated, high yields can be expected. If the first application of nitrogen fertilizer contained a lot of sulfur, it is better to use nitrogen fertilizers without sulfur in the following applications.
Where can you buy fertilizers to overcome the most common nutrient deficiencies in plants? Local garden centers and hardware stores sell a wide variety of fertilizers. Also, Amazon sells a wide assortment of fertilizers for outdoor and indoor plants.
You might also be interested in our story about How to Fertilize Clematis and Other Flowering Plants.