Practices to Help Combat Pests and Diseases

Nursery hygiene is a job that needs to be kept up throughout the year, according to  Carl Mason, our Technical Advisor for North East England.

March 15, 2022

The statement “Start Clean, Stay Clean” is a very good place to start. The reasons being to keep pest and disease populations down to the minimum while eradicating pathogens that cause so many problems when plants become stressed or weak. 

The key principle is to clean and reset the growing area back to a neutral state, where new plants have the best start in life.  As we are all aware, the plant protection chemistry at our disposal is reducing at an alarming rate, making it increasingly challenging to control pest and disease outbreaks.  This makes it more important than ever to select the right products and use them at the correct rates to disinfect structures, irrigation lines, spray tanks, and even people! 


  1. It is good practice to ensure all groundcover, walls, and paths are free of weeds and the area is swept between plants, as this reduces pest and disease risks. It is advisable to use a quality disinfectant, at the correct rate, and treat all areas—including walls and paths—before bringing in the next plants. 
  2. In an ideal world it is best to use new pots, packs, and if possible, bases. However, at a time when it is important to recycle where possible pots, packs, and bases that are being reused must be washed to remove all organic matter, before being disinfected. Always read the product label as some disinfectants require a period of being wet before pots are refilled with growing media. 
  3. To avoid a build-up of algae on and inside the structure, glasshouses and tunnels should be washed down annually and disinfected regularly. This will also pay dividends in helping to control a range of pests, such as whitefly and red spider mite. 
  4. Irrigation lines require cleaning and flushing out. This not only kills pathogens living in the pipes, but also helps remove any build-up of feed or limescale. Again, use an appropriate quality cleaning solution, at the correct rate. This process is most effective and safe when carried out between plants. 
  5. Spray tanks should always be washed out after use. This is particularly important if the tank is being used to apply biological nematode controls, as any chemical residue could damage these beneficial organisms. 
  6. When it comes to biosecurity, it is good policy to ensure all visitors sign in and use a foot bath before going onto the site. Indeed, all staff need to take care, i.e., use the foot baths and wear gloves to minimize the risks of transferring pathogens between plants. 

While this does not aim to be an exhaustive list of nursery hygiene measures, it highlights the six basic practices all nurseries should adopt to help combat pests and diseases. Of course, depending on the plants being grown, you may want to intensify your protocols to suit your site.   

It is important to accept that the days of the curative chemicals are on the way out, so becoming more proactive from the start is the sensible way forward.