DeficiencymediumMay–Aug

Manganese deficiency

Mangan-Mangel

This description was machine-translated.

How to spot it

Manganese deficiency shows itself as a net like chlorosis: the leaf veins stay green while the areas between them fade to light green or yellow. The damage appears first on the younger and middle leaves in the upper part of the shoot and at first glance resembles iron deficiency, but differs through fine brown dots in the paled tissue. Affected above all are ericaceous plants such as blueberry, rhododendron and azalea, as well as grapevines, usually on soils with too high a pH. Where the shortage is stronger the shoot stays weak and leaves drop early.

Prevention

With blueberry, rhododendron and azalea make sure the soil stays permanently acidic with a pH of 4.5 to 5.5; liming such beds is out of the question. In container culture water only with lime free water, for example collected rainwater instead of hard tap water. Loosen the soil on wet, cool sites and provide good drainage, so that the roots can take up nutrients better. Grapevines and raspberries benefit from mulch layers of pine needle litter or bark compost, which acidify the soil gradually.