Azalea: Lime-induced chlorosis

Biology

Lime-induced chlorosis, or leaf yellowing, is caused by alkaline soil conditions. High alkalinity of soils can make iron or manganese unavailable to plants, causing leaf chlorosis. Pale to bright yellow leaves, particularly on the new growth, are common symptoms. Typically the chlorosis begins at the edges and progresses into the leaf, with only the veins remaining green in severe cases. Plants near new concrete may also suffer from lime-induced chlorosis.

Management Options

Use Integrated Pest Management (IPM) for successful plant problem management.

Non-chemical Management

Select non-chemical management options as your first choice!

• Adjust soil pH to 4.5-6.0. Addition of sulfur or organic matter, especially conifer needle mulch, which is highly acidic, may be beneficial. Work soil under plant carefully to avoid damage to the shallow root system.
• Use iron chelate, either as a soil treatment or by foliar feeding to quickly help chlorotic plants. Read and follow all label instructions.
• Check plant’s proximity to newly poured concrete. New concrete leaches lime into the surrounding soil, raising the pH.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

• None recommended