Feeding

Reading nutrient deficiencies by leaf color

Spot the early signs and correct your feeding schedule in time.

Identifying nutrient deficiencies through plant leaves is essential to act in time and maintain a healthy vegetable garden. Alterations in color, spots or deformation of the foliage are clear signs that the plant is not receiving the minerals essential for its development. **Visual Diagnostic Chart by Nutrient** | Nutrient | Main Symptom on Leaf | Location on Plant | |---|---|---| | **Nitrogen (N)** | Uniform yellowing throughout the leaf (chlorosis). | Old Leaves (Lower Zone) | | **Phosphor (P)** | Dark green, purple or reddish tones on edges and veins. | Old Leaves | | **Potassium (K)** | Yellow edges that then turn brown and dry (burnt look). | Old and Medium Leaves | | **Magnesium (Mg)** | Yellowing between the veins, keeping the veins green (intervenal chlorosis). | Old Leaves | | **Iron (Fe)** | Intense yellowing or white between bright green veins. | Young leaves (upper zone) | | **Calcium (Ca)** | Deformation, curly ends or necrosis on the edges and new shoots. | Young Leaves & Buds | | **Sulphur (S)** | Pale green or uniform yellow colour (similar to nitrogen). | Young leaves | **How to Interpret Plant Signals** * **Mobile Nutrients (N, P, K, Mg):** The plant displaces the available nutrients towards the areas of new growth. Therefore, the symptoms of lack of these minerals first appear in the **old leaves** on the underside. * **Immobile Nutrients (Ca, Fe, S):** The plant cannot move these elements from one area to another. If they are missing in the substrate, the **young leaves** at the top will show damage immediately. **Steps to Correct Deficiencies** 1. **Adjust the pH of the substrate:** On many occasions, nutrients are present in the soil but cannot be absorbed by the plant due to a pH that is too acidic or alkaline. Keep the pH between 6.0 and 6.8 for most crops. 2. **Check watering:** Excess water suffocates the roots and prevents the absorption of minerals, simulating a lack of nutrients. 3. **Apply specific fertilizers:** * **For Nitrogen:** Apply compost, worm castings or blood meal. * **For Potassium and Phosphorus:** Use wood ash (sparingly) or bone meal. * **For Iron and Magnesium:** Use iron chelates or Epsom salts (magnesium sulfate) diluted in water. * **For Calcium:** Add crushed eggshell or agricultural lime to the substrate.