Do the leaves and stems have black spots on them?
Are there any rust-colored spots on foliage?
Are the leaves covered with white powder?
Are the leaves curled and distorted?
Do the leaves and flowers have holes?
Are the leaves covered in coarse stippling and may appear silvery?
Are the leaves covered with small bumps?
Black spots surrounded by yellow patches are caused by fungal disease - Black spot. Prune off and destroy all diseased leaves and clean up all fallen ones. If possible, avoid wetting the leaves when watering. For severe infections, the recommended control is weekly applications of sulfur.
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.
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 below to keep foliage dry. Any affected leaves should be cut off and removed. The appropriate fungicidal spray will protect your plant from further infections.
Distorted and curled leaves are caused by aphids. These tiny insects cluster under leaves and on growing tips where they feed on plant sap. 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. 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.
These symptoms indicate thrips. Severely infected plant parts should be removed and destroyed. Control thrips by introducing lady beetles or lacewings, their natural predators. Insecticidal soap helps in severe infestations.
Leaves covered by small bumps are caused by scales. 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.
Various caterpillars attack Carolina roses, and make holes in their leaves. You can handpick and destroy them if the infestation is not severe. BTK spray will help in controlling caterpillars.
https://www.thespruce.com/how-to-grow-and-care-for-the-carolina-rose-5076021
Ellis, B. W., Bradley, F. M., & Atthowe, H. (1996). The Organic gardener's handbook of natural insect and disease control: a complete problem-solving guide to keeping your garden & yard healthy without chemicals. Emmaus, Pa.: Rodale Press.
Sreten null
Hi! I’m Sreten Filipović. I graduated from the Faculty of Agriculture at the University of Belgrade, with a master's degree in Environmental Protection in Agricultural Systems. I’ve worked as a researcher at Finland's Natural Resources Institute (LUKE) on a project aimed at adapting south-western Finland to drought episodes. I founded a consulting agency in the field of environment and agriculture to help farmers who want to implement the principles of sustainability on their farms. I’m also a founding member of the nonprofit organization Ecogenesis from Belgrade whose main goal is non-formal education on the environment and ecology. In my spare time, I like to write blog posts about sustainability, the environment, animal farming, horticulture, and plant protection. I’ve also published several science-fiction short stories.
You can find me on LinkedIn at https://www.linkedin.com/in/sreten-filipovi%C4%87-515aa5158/
