As garden mums approach the final stages of production, growers shift their focus from building healthy crops to preserving quality until they reach the sales floor. Uniform size, strong branching and an attractive finished appearance are all key factors in delivering market-ready plants for fall sales. A successful finishing strategy can help growers maintain plant quality through shipping, retail display and consumer purchase. 

Protect Mums from Late-Season Pests and Disease

Even as mums approach finish, they remain vulnerable to common insects like thrips, aphids and caterpillars. These insects can damage foliage and blooms while also spreading viruses, making continued scouting essential through production. 

Disease pressure can also persist late in the season. Root rot caused by Pythium spp. and Fusarium are common challenges, especially under warm, wet conditions or when plants experience stress. Maintaining a consistent scouting program, along with rotating insecticides and fungicides, can help protect crop quality while supporting resistance management. Products such as Postiva™ fungicide can help provide protection against key diseases including Fusarium, while Vykenda^® insecticide/miticide can help manage challenging insect pests like thrips as crops move toward finish. If activity by caterpillars is observed, a spray of Mainspring^® GNL insecticide or Acelepryn^® insecticide may provide protection for three to four weeks.

Fusarium, early stages. Syngenta photo.	Fusarium, late stages. Syngenta photo.

Prevent Late-Season Stretch

Incorporating a plant growth regulator (PGR) late in production can help ensure mums maintain their ideal size, shape and overall quality through shipping and retail display. Without proper growth regulation, plants are more susceptible to late-season stretch, which can reduce marketability. 

Bonzi^® ornamental growth regulator offers flexible application options to help growers deliver finished plants that meet retail expectations. When applied as a spray or drench, Bonzi helps:

• Maintain compact growth by reducing stem elongation
• Improve plant appearance with deeper green foliage and enhanced flower quality
• Extend shelf life for improved post-production performance

Application timing is critical for consistent results. Drench applications should be applied three to four weeks before finishing to minimize undesired stem elongation. Growers can fine-tune their approach using the Bonzi drench guide, which provides detailed guidance on rates based on production goals.  

By combining season-long pest management with targeted finishing strategies — including growth regulation — growers can produce uniform, high-quality mums that stand out at retail and maintain their quality and appearance throughout the fall season. 

Stay ahead of late-season stretch and learn more about finishing mums with Bonzi at GreenCastOnline.com/Bonzi.


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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. Acelepryn^®, Bonzi^®, GreenCast^®, Mainspring^®, Postiva™, Vykenda^® and the Syngenta logo are trademarks of a Syngenta Group Company.