DISEASE
 
   NAME
     Chlorosis in Azaleas
     Iron Deficiency

Description
Lack of available iron in the soil or if the soil is too alkaline for the absorption of iron.

Symptoms
The interveinal areas of young leaves become yellowish to white and the margins may become dried. Affected leaves may be smaller than normal and fall prematurely. Twigs and new branches may suffer from dieback.

Favoured Conditions
It is more prevalent in alkaline soils or soils that have had excessive lime added. Planter beds in and around concrete suffer from leaching.	

Affected Plants
A wide range of plants that prefer acid soils, these include Azaleas, Hydrangeas, Gardenias and Euphorbia pulcherrima, Dillenia indica. All are susceptible to chlorosis.

Non-chemical Control
For infected plants apply iron chelates slowly over several weeks in dilution, on the soil and foliage. As a preventative measure, do not apply lime, superphosphate or ash to the soil and when fertilising select a type suitable for acid loving plants, such as blood and bone.

Chemical Control
Iron sulphate or iron chelates can be applied either to the soil or to the leaves as a foliar spray.