Roses remain a popular crop among growers, valued for their wide range of shapes, sizes and vibrant colors. Whether grown for cut flower arrangements, patio containers or garden transplants, their versatility continues to drive high market demand. However, because roses are grown year-round in both greenhouses and outdoor nurseries, they are exposed to a variety of seasonal challenges, such as mites, downy mildew and powdery mildew.

To protect crop quality and meet production goals, proactive management is essential. A strong agronomic program combined with proven cultural practices forms the foundation for preventing insect and disease outbreaks and supporting healthy, attractive rose production.

Watch for Signs and Symptoms of Threats

While year-round availability is ideal for growers and retailers, disease and insect threats can harm plant health and complicate production. Early into production, growers should begin checking plants for presence of pests and signs of infection.

• Spider mites feed on the undersides of leaves leading to pale yellow stippling of the foliage due to chlorophyll loss. Continued feeding causes leaves to turn yellow and defoliate, reducing plant vigor.
• Downy mildew is a serious disease that begins with yellow or purple leaf discoloration, often within the veins. Additional symptoms to look out for are pale foliage with yellow, tan or reddish blotchy areas, distorted or downward curling leaves, and a light gray or purple fuzz on the undersides of leaves.
• Powdery mildew is caused by fungal pathogens that form white, talcum-like colonies on plant surfaces, appearing on leaves, stems and flowers. Advanced infection leads to yellow and brown leaves, premature leaf drop and reduced plant vigor.

Space, Scout and Select a Strong Agronomic Program

Whether roses are grown in a greenhouse or outdoor nursery, proper plant spacing is critical for encouraging airflow, reducing canopy humidity and minimizing the risk of foliar diseases. Consistent scouting within the canopy and on leaf undersides enables early detection of pests and diseases before they impact crop quality.

Agronomic programs, like the Rose Agronomic Program from Syngenta, provide a strategic framework for success, offering guidance on product rotation, optimal application timing and mode-of-action diversity. This integrated approach supports healthy, resilient roses and helps ensure season-long protection in any production environment.

To learn more about the tools available to help grow healthy, attractive roses, visit GreenCastOnline.com/Solutions.

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