POTASSIUM (K) Affected plants are usually tallest and appear to be most vigorous. Necrotic spots form on lower leaves. Red stems. Leaves appear pale or yellow. Add chemical fertilizer containing K.
MANGANESE (Mn) Necrotic and yellow spots form on top leaves. Mn deficiency occurs when large amounts of Mg are present in the soil. Foliar feed with any chemical fertilizer containing Mn.
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