Now is the Time to Treat Iron Deficiency

Iron chlorosis is a common problem of many ornamentals, shrubs, vines and trees. Instead of a healthy, rich green look, the leaves of trees, plants and shrubs affected by iron chlorosis are yellow to light green, with prominent veins. In severe cases, iron chlorosis will cause the leaf to take on a scorched look. 

This yellowing of normally green leaves is due to a lack of chlorophyll, brought on because the plant or tree involved is lacking the micronutrient Iron. The root cause of iron deficiency is directly related to the quality of the soil your trees and shrubs are planted in. Remedies for iron chlorosis include applying iron supplements in a form the tree can use, as well as improving soil structure, reducing soil pH and building stronger root systems. 

Iron supplements are available in liquid and granular forms. Choose one that is labeled Chelated. Chelated iron is not affected by soil pH levels and as a result, is more readily available to your trees and shrubs. The best iron supplement choice is a complex of iron and the chelating agent EDDEHA. 

These supplements can be applied directly to the soil under the tree; through a series of holes drilled around the drip line; by trunk injection; by foliar application with a sprayer. The method selected depends on where the tree is planted in your landscape. To fix the problem long-term, you have to fix the soil.   

Applying organic materials such as compost, peat moss and humate will improve soil structure and reduce alkalinity. Each of these products is applied to the area under the tree's dripline, three to four times per year. Finally, know what you’re dealing with. This shrub may look like chlorotic, but yellow leaves are normal for a Gold Flame Spirea.