The key to successful greenhouse plant production is to start clean and stay clean. Regularly cleaning production areas, removing plant debris and applying sanitizing agents are essential practices to protect against insects and diseases for healthy plant growth.

For example, debris can contain spores and pathogens that quickly lead to new infections. Similarly, weeds growing in production areas can serve as hiding spots for insects like mites and whiteflies, creating a breeding ground for outbreaks to spread throughout the greenhouse.

How to Clean

To properly sanitize a greenhouse between crops:

• Remove all plant debris: Start by thoroughly clearing debris along the walls, floors, benches and under-bench areas. Any remaining organic material may reduce the effectiveness of sanitizing agents.
• Choose the right sanitizer: After debris removal, select a sanitizing agent such as quaternary ammonium or hydrogen dioxide-based products. These are effective against pathogens and less corrosive than a traditional 10-20% bleach solution.
• Apply correctly for best results: Carefully follow label directions and apply the proper concentration of sanitizer to clean hard surfaces in the early morning or evening, avoiding the hottest part of the day. Ensure the solution remains wet for 10–15 minutes to effectively kill pathogens.
• Consider the flooring type: Cement or ground cloth under benches simplifies cleaning and disinfection. Gravel or bare soil can be difficult, but still possible with careful cleaning and application.

Additionally, it’s important to keep an eye out for algae growth. While all areas of production may have algae present, propagation areas will accumulate fastest, not only creating new breeding grounds for pests such as fungus gnats or shore flies, but also slip hazards for workers.

How to Maintain Cleanliness

Practices including minimizing organic debris, sanitizing production areas and limiting algae growth is the first line of defense against insects and diseases that threaten greenhouse plant production.

To maintain cleanliness, consider products like Citation^® insect growth regulator (IGR) that help control insects like leaf miners, fungus gnats and shore flies. Citation is used as a drench to the planting media to stop larvae from feeding and causing injury to plant roots. It can also be applied under benches and in areas with signs of feeding.

There are also biological controls, such as predatory mites like Hypoaspis miles, to manage pest populations naturally. Whichever method you choose, it is essential to frequently inspect plants to detect and address issues early to protect current and future production.

To learn more about the tools available for greenhouse sanitation, visit GreenCastOnline.com/Ornamentals.

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