Use plastic mulch to warm the soil. Phosphorus deficiency causes small and rigid leaves, the plant habitus is very erect. Leaf edges showing potassium deficiency. Growth is sparse, thus the plant shows a spindly appearence. Phosphorous is one of the three primary nutrients required by plants in relatively large quantities and is essential for cell division, strong stems, and good root development. TOMATO PLANT Phosphorus deficiency Growth dwarfed and thin; leaflets droop, curl backward and develop strong, dull purple tints. Phosphorus is abundant in our soils but may be unavailable to the plant when the soil is too cold. 253. Phosphorus (P): essential for healthy roots and also for fruit to ripen. Some leaves may be affected by all three mineral deficiencies at the same time! When I was new at this, the sight greatly perturbed me. ... Classic symptoms of calcium deficiency include blossom-end rot of tomato. Purple leaves usually indicate phosphorus deficiency. Leaves with P deficiency are usually dark green to bluish green in color. Phosphorus deficient plants develop very slowly. Donât plant tomatoes too early in the season. Exposure to intense light can also cause purple leaves on tomato plants. Total height is almost normal. The bottom leaves show interveinal chloroses and necrotic leaflets. Reasons Phosphorus deficiency. TOMATO STEM Calcium deficiency Death of growing point and die-back of main stem from tip; die-back of leaves, progressing from terminal leaflets and of flower and fruiting trusses. Plants develop a distinct purpling of the stem, petiole and the under sides of the leaves. There are also pests and diseases that can cause leaves to turn purple. Phosphorus deficiency causes small and rigid leaves, the plant habitus is very erect. Many times, there is plenty of phosphorus in the soil, but the plant can't get to it. The bottom leaves show interveinal chloroses and necrotic leaflets. Phosphorus deficiencies (Figure 1) occur early in the growing season when soil is still cool. Reasons Phosphorus deficiency Leaves with P deficiency are usually dark green to bluish green in color. Lack of phosphorus shows up when growth is poor, leaves begin to have a blue/green tint or fall off and fruit and flowers are disappointingly small or late. Total height is almost normal. As a soil grower, I knew that purple under leaves and veins on plants meant either a phosphorus deficiency or a disease. Phosphorus deficiency causes small and rigid leaves, the plant habitus is very erect. This phenomenon has occurred with almost every tomato variety, and some other non-tomato plants, that I have grown in my passive wick Hydrosock Plain 2 Grow System. Common Tomato Problems. This lovely purple tint is a classic symptom of phosphorus deficiency in a tomato seedling. As the deficiency worsens, the purple color becomes more noticeable. Growth is sparse, thus the plant shows a spindly appearence. Under severe deficiency conditions there is a tendency for leaves to develop a blue-gray luster. 252. Growth is sparse, thus the plant shows a spindly appearence. Tomato Plant Leaves and Nutrient Deficiencies. A phosphorus deficiency will cause the leaves on a tomato plant to turn purple, especially if the plant is young or if temperatures are low (below 60 degrees Fahrenheit). Reasons Phosphorus deficiency Leaves with P deficiency are usually dark green to bluish green in color. Total height is almost normal. Magnesium deficiency on tomato leaf. Potassium (K): vital for flower and fruit growth. Phosphorous. The bottom leaves show interveinal chloroses and necrotic leaflets.