Apart from pest and disease attacks which we covered in a previous blog, Plants can also suffer from nutrient deficiency! In this blog, we cover deficiency symptoms of the main nutrients required by a plant.
Any plant essentially needs ‘17’ mineral nutrients to grow, live and reproduce. A deficiency in any one of these nutrients would affect the plant’s ability to complete its normal life cycle. Hence one needs to be cautious when feeding the plants.
- Basic nutrients:
Carbon (C), Oxygen (O) and Hydrogen(H)
Nitrogen (N), Phosphorus (P), Potassium (K), Calcium (Ca), Magnesium (Mg) & Sulphur (S)
- Micro/Trace elements:
Boron (B), Chlorine (Cl), Copper (Cu), Iron (Fe), Manganese (Mn), Molybdenum (Mo), Zinc (Zn) and Nickle (Ni)
Symptoms and their interpretation:
Plants have their own mechanism to express nutrient requirements by showing “symptoms” of deficiency or toxicity (over-feeding). In a sense, this is a plant’s voice or body language and can even reveal to us which mineral is deficient!! It is essential for us to interpret and remedy.
- Mobile elements: N, P, K, Cl, Mg, Mo
If the mineral element is mobile in nature, it’s deficiency/toxicity appears in the older part of the plant as the elements travel to different parts of the plant
- Immobile elements: S, B, Fe, Zn, Ca, Cu, Mn, Ni
If the mineral element is immobile in nature, the elements get locked, and therefore, deficiency symptoms mostly appear in the growing region of the plant.
Signs/symptoms of different nutrient deficiencies
- Nitrogen: Yellowing (chlorosis) of older leaves gradually progress to newer leaves, along with slow and stunted growth in plants. Nitrogen deficient plants will mature early, quality and yield are reduced.
- Phosphorous: Leaves & stems of Phosphorus deficient plants are generally dark green in colour. Older leaves turn yellowish with a pink/purplish margin.
- Potassium: older leaves show chlorotic (yellowing) areas with burnt margins (scorch) along the leaves. It progresses along the leaf margin towards base leaving the midrib alive and green.
- Calcium: Development of dark green leaves with leaf distortion. Leaf tips become brittle and dry and eventual wither and die
- Magnesium: Most common symptom of Mg is interveinal chlorosis (yellowing of leaves in between the veins, yet veins remain green colour) in younger leaves and leaf margin become yellow or reddish-purple while the midribs remain green.
- Sulphur: Sulphur deficiency occurs in younger leaves. Leaves turn green to yellow in colour. Plants will be small and spindly in stature and stems are thin.
- Iron: Iron deficiency characterized by interveinal chlorosis with a sharp distinction between veins and yellowing areas of younger leaves. In severe conditions of deficiency leaves become whitish yellow in colour, tissue becomes brown and dies (necrosis) leading to slow plant growth
- Manganese: Manganese deficiency also causes interveinal chlorosis in young leaves, but there will be no sharp distinction lines exist between veins and yellowing areas, but rather a more diffuse chlorotic effect
- Boron: Growing young leaves become yellow and the death of terminal growing region. Additionally, we can see dark brown and irregular spots on the plants in case of severe deficiency
- Copper: Plants show chlorosis of younger leaves with stunted planted plant growth. This deficiency causes tip burns in many vegetable crops . Ex: Tip burn in lettuce.
- Zinc: Interveinal chlorosis especially midway between the leaf margin and midrib. Plants with Zinc deficiency show severely stunted growth as Zinc helps in elongation of internodes, which will be affected. At critical stages, plant tissue become grey-white in colour and eventually dies.
- Nickle: Signs of chlorosis and interveinal chlorosis in young leaves leads to necrosis
- Chlorine: Typical signs of chlorine insufficiency leads to wilting of leaves at leaf margin and highly branched root system, especially in cereals. General sings like yellowing and dark brown patches with the demarcation between dead and live tissue.
- Molybdenum: Deficiency symptoms almost resemble Nitrogen deficiency symptoms showing chlorosis and stunted growth in plants. Other signs to look for may be scorching, cupping or rolling of leaves. Molybdenum deficiency in cauliflower causes ‘Whiptail’- a distinguished deficiency, wherein leaves become thick, brittle and eventually wither, leaving only the midrib portion of leaf to remember the shape of ‘tail’
Do keep a look out for these symptoms and give your plants proper care and maintenance!
Sushma completed her B. Sc. from College of Horticulture, Hiriyur and M. Sc. from College of Horticulture, Bengaluru. She is an avid gardener with expertise across soil based and soilless gardening techniques using substrates.