What Is Wrong With My Rugosa Rose?

Are there any circular water-soaked or brown lesions on older leaves, centers of lesions become bleached as they mature?

Are the leaves covered with white powder?

Are there any rust-colored spots on foliage?

Are the leaves yellow and covered by small bumps?

Are the leaves curled and yellow?

Are the leaves discolored, foliage may be webbed?

Black spot is a fungal disease spread by wind and rain. Disease emergence is favored by cool weather interspersed with moisture from dew or rain. The disease may require applications of appropriate fungicides for adequate control.

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.

Rust-colored spots on foliage indicate 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.

Yellow leaves covered by small bumps are caused by scales. These tiny, shelled insects often feed on the undersides of the leaves, causing an unhealthy appearance with yellowish blotches on the upper leaf surfaces. Scrape off minor infestations with your fingernail. Prune out badly infested growth, or use a soft brush and soapy water to gently scrub the scales off the stems. Control scales by spraying insecticidal oil during the growing season.

Distorted, curled leaves are caused by aphids. These tiny insects can vary in color, green, pink, black, gray to completely white. They 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.

Spider mites are known to cause problems for rugosa roses. You can control spider mites by spraying plants thoroughly with water 2-3 times a day for several days. For severe infestations, spray plants with insecticidal soap or pyrethrin.

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.