If symptoms appear on new leaves, the problems could related to iron, zinc, manganese, copper, boron, calcium, or sulfur.
Deficiency: Young leaves will be mottled, spotted with yellow and brown areas. dead spots will appear, leaves will yellow, veins remain green. rumored that leaves can have a checkered pattern. This really only happens in young/new growth.
may become yellow in between the veins, with mottled brown spots on the
affected leaves. These brown dead patches may spread and eventually
kill the leaf. Leaves may also shred and fall apart. Overall growth of the marijuana plant may be stunted. Manganese deficiencies are often caused by a pH that is too high, or if the plant is getting too much Mg in the soil.
When a plant is deficient in manganese, the top leaves of the plant are afflicted. The top leaves of the plan will begin to yellow and die when there is a prolonged deficiency of this nutrient.
Necrotic and yellow spots form on top leaves. Mn deficiency occurs when
large amounts of Mg are present in the soil or pH is to high. Foliar feed with any
chemical fertilizer containing Mn. And correct any pH problem you may have.
Picture 1 shows a manganese deficiency in flowering.