Why Does My Aronia Tree Look Unhealthy?

Are the leaves pale on their upper side and are there any dusty blisters on the undersides?

Are the leaves covered with white powder?

Are there any oozing cankers on the branches and buds?

Are the leaves curled and distorted?

Do the leaves and flowers have holes?

Are there any yellow leaves on individual canes in late spring?

Are the buds, flowers, and seed pods malformed and prematurely fallen off?

Likely cause for these symptoms is a fungal disease - Rust. Provide good air circulation around plants by thining them. Avoid making leaves wet when watering. All infected leaves should be removed. Spray leaves with sulfur early in the season to prevent rust or to treat mild infections.

White, powdery patches on the leaves are caused by a fungal disease Powdery mildew. Powdery mildew usually appears in damp places. Encourage good air circulation around the affected plants by thining them and any surrounding plants. Water plants from bellow to keep foliage dry. Any affected leaves should be cut off and removed. The appropriate fungicidal spray will protect your plant from further infections.

Oozing cankers on the branches and buds are caused by bacterial blight. The spread of the disease is greatest during humid, wet weather conditions. Practice good garden hygiene at the end of the season and discard, do not compost, possibly diseased plants and plant parts. Space plants to allow for adequate air circulation. Prune all infected branches below cankers.

Distorted and curled leaves are caused by aphids. These tiny insects cluster under leaves and on growing tips where they feed on plant sap. Leaves, stems, and buds get distorted and later leaves and flowers drop from the plant. You can control them by washing them off the plant with water spray. Insecticidal soap should be used with severe infestations.

Holes in leaves and flowers are caused by Japanese beetles, pests that can seriously damage foliage. Adults of these insects devour leaves, stalks, and flowers of nearly 300 plant species. Their larvae feed on the roots of the plants. Handpick adult beetles into a can of soapy water but make sure to wear gloves as Japanese beetles are blister beetles. Apply parasitic nematodes to the soil to limit beetle grub populations. Use pyrethrin powder or neem oil as a last resort.

Yellow leaves on individual canes in late spring are the first symptoms of Cane borers. The cane will die in summer. The larva is a pale yellow worm. The female borer lays eggs on the canes in early June. The worm hatches and bores into the cane and feeds all season. Remove and destroy infested canes as soon as possible.

These symptoms usually indicate Stink bugs. Adults are flat, shield-shaped, green, blue, or red insects that emit a sharp odor when crushed. Handpick these pests to control mild infestations. Spray plants with pyrethrin if the injury is serious.

If leaves and stems have been eaten whole the problem may be deers. If deer frequent your property then your plants are in jeopardy. Barriers provide the most reliable long-term protection from deers.