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Get the most from bioinsecticides with these three top tips

Are you struggling to get the desired results when using bioinsecticides? Read our three top tips for planning your spray programme

Close up of water droplets on plant leaves

New sustainable forms of crop protection, such as bioinsecticides, are quickly becoming central to pest control programmes. Generally, biopesticides present a lower risk to the environment and when used correctly can have extremely positive results. 

Yet, we regularly hear from growers that they struggle to achieve the desired results. So, here are three top tips to help you get the best outcome when using biopesticides. 


1. Get the basics right

With any plant protection product, it is important to get the basics right. This is especially true when it comes to biopesticides. The first step to success is ensuring the product is stored correctly. Many biopesticides contain a living active ingredient such as a fungus or bacteria. These will often need to be cold-stored and kept in a sealed container to ensure the living active ingredients remain as dormant as possible. 

Before applying a biologically-based product, it may be necessary to ‘wake up’ the living active ingredient. This is often done by presoaking the product in a reduced water volume for a few hours. This kick starts the germination process and ensures that when the spray is applied the active ingredient is ready to take effect.

Before applying the product, it is also important to ensure the spray equipment is clean and as free as possible from pesticide residues. If you are applying a fungal based biopesticide in a tank that has residues from fungicides, this is likely to negatively impact performance. It is recommended that you wash your tanks properly and use spray tank cleaners where appropriate. Indeed, growers sometimes opt to use a separate spray tank for biopesticides.


2. It’s all about the timing 

Generally, biologically-based products are best applied at low population pressure. They often require contact and can take several days to work. In high population pressures, ensuring enough contact with pests when they are layered is very difficult. Also, environmental conditions can often allow for pests to move through their life cycle quickly enough to reproduce before they are controlled by a fungal infection. 

Although biopesticides are generally best applied at low population pressures most should not be applied before the presence of pests has been confirmed, this is because these products tend to be contact acting and will have a very short persistence in the crop. They are best thought of as an early cure, which makes monitoring and forecasting even more important.

As previously mentioned, active ingredients in biological products are often living organisms. Some will require certain temperature and humidity conditions to perform effectively. Distributors will normally stock informational booklets detailing the conditions needed for individual products. 

Pest biology has always been an important part of crop protection, knowing when and where you are likely to find a first infestation can help you stay ahead of the game. Knowing what the pest's life cycle is and what the dominant stage you are recording in your crop can allow you to make a more informed decision on when and what biopesticide to use. 


3. Make sure you plan ahead

It’s important to think about your spray programme and what subsequent sprays will follow a biopesticide application. This is a similar concept to having a clean tank, if you spray a fungicide closely after a biopesticide there is the potential to knock down the fungal element in the biological product. Some products will have guidance on the label and technical notes advising the number of days between applying the biopesticide and then applying certain conventional chemistry. But as a rule of thumb, if the products can't be mixed in a tank, it would seem unwise to apply them too close together in a programme.

With biopesticides, product and target pest knowledge is the key to getting effective results. Working alongside your agronomist to understand the key issues on your site and what biopesticides should be used in the winter will mean that come spring you will be ready to implement your spray programme successfully. Fail to prepare, prepare to fail rings very true when it comes to biopesticides.


If you would like to speak to the Fargro Technical Team please call us on 01903 256856 or email


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