Michigan State University Extension
Ornamental Plants plus Version 3.0 - 00001632
11/12/99
Iron deficiency
Iron deficiency in landscape plants that require an acid
soil will cause young leaves to turn yellow while the main
veins remain green. In advanced stages, brown spots occur
between the leaf veins.
Plants commonly affected by iron deficiency are pin oak,
azalea, blueberry, rhododendron and holly.
To treat plants, spray them with iron chelates. These are
available from most nurseries and garden centers and
provide a suitable solution for small plants. Spraying
large trees is not practical.
Use trunk implants of soluble iron sources on trees. The
plastic capsules are inserted into holes drilled in the
trunks. As the trees grow, they cover the capsules. The
disadvantage of this method is the necessity of drilling
the holes in the tree trunk to make the implants. Trees
vary in their ability to tolerate repeated wounding.
Drilling a series of holes in the trunk every two to three
years may become a more serious problem than the
deficiency. Keep trees with implants well watered and
fertilized so they heal as quickly as possible.
Adding fertilizer that contains iron to a soil that is not
sufficiently acid will not help. The plants roots will
not absorb the additional iron until the soil is made more
acid.
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to commercial products or trade names does not imply
endorsement by MSU Extension or bias against those not
mentioned. This information becomes public property upon
publication and may be printed verbatim with credit to MSU
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a commercial product or company.
This file was generated from data base ZZ on 01/19/00.
Data base ZZ was last revised on 11/12/99.
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