Producing healthy garden mums during the summer can be challenging for nursery and greenhouse growers. Many mum crops are produced outdoors or under limited environmental control, leaving them highly susceptible to conditions that favor pest development. As crops progress through production, proactive insect and disease management becomes critical to protecting plant quality. 

Establishing a planned insect and disease management rotation early helps growers manage pressure throughout production while supporting long-term resistance management objectives.  

Key Insects and Diseases to Scout Early

Mum production faces disease and insect challenges as summer conditions intensify. Two of the most common diseases affecting mums are root rots caused by Pythium spp. and Fusarium wilt caused by Fusarium oxysporum. These diseases are often associated with environmental stress and may become established before symptoms are easily detected.

Pythium infections occur more frequently during periods of warm temperatures and excessive moisture. Infected plants may appear lighter green, be smaller and wilt during the heat of the day, even when growing media is moist. As symptoms progress, lower leaves may yellow and drop. 

Fusarium symptoms typically appear later in the season, but infections begin much earlier in production. When symptoms develop, sections of the canopy may lighten in color and wilt from the bottom up, highlighting the need for season-long management. 

Fusarium sporodochia, Syngenta	Internal vascular discoloration, Syngenta

Insect pressure is also a consistent concern in mum production. Thrips, aphids and worms can impact plant quality if not managed early. Thrips are especially problematic because of their ability to spread Tomato Spotted Wilt Virus (TSWV) and cause feeding injuries like scarring and distortion. Aphids pose similar risks, spreading Chrysanthemum Virus B (CVB) as populations increase rapidly under warm conditions. 

Loopers, armyworms and other lepidopteran pests feed aggressively on terminals and foliage. Monitoring moth activity and inspecting growing points regularly can help growers identify pressure before feeding becomes severe. 

Build Control with a Rotational Strategy

Effective insect and disease management often requires more than a single application. Rotating products with different modes of action helps deliver consistent control and reduces the likelihood of resistance. The Mum Agronomic Program is designed to guide pest management decisions throughout the production cycle based on crop stage, pest pressure and resistance management considerations. 

For disease management, Postiva™ fungicide is featured in the program to provide robust protection against key soilborne and foliar diseases, including Fusarium. An excellent rotation partner to diversify programs, Postiva helps deliver strong, reliable management of difficult diseases through production. 

Vykenda^® insecticide/miticide is also a key component of this program. An IRAC Group 30 insecticide, Vykenda features a unique mode of action that works through contact and ingestion to rapidly stop feeding and control challenging insects such as mites, thrips, red-headed flea beetles and black vine weevil adults. Vykenda is a strong rotation partner with Mainspring^® GNL insecticide, which is powered by cyantraniliprole in IRAC Group 28. When used together, these products help diversify insect control strategies to support effective resistance management. 

Support Crop Quality Throughout the Season

Incorporating product rotations into a comprehensive agronomic program can help reduce crop stress and support consistent growth during the most challenging production periods. 

Get ahead of season-long insect and disease pressure by downloading an effective agronomic program at GreenCastOnline.com/Solutions.


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© 2026 Syngenta. Important: Always read and follow label instructions. Some products may not be registered for sale or use in all states or counties and/or may have state-specific use requirements. Please check with your local extension service to ensure registration and proper use. GreenCast^®, Mainspring^®, Postiva™ and Vykenda^® are trademarks of a Syngenta Group Company.