With vine weevil grubs emerging from eggs laid in early summer, autumn is a key time to apply beneficial nematode controls - says ICL Technical Area Sales Manager - Sam Rivers.  

“In unprotected containerised stock, the grubs (larvae) overwinter in the growing media feeding on plant roots, often leading to major plant losses,” he warns.  “With Exemptor no longer available, all UK growers must now embrace an IPM approach to control this pest.”   

Handily incorporated in growing media mixes, Exemptor provided up to 38 weeks of effective control.  With it being close to more than 38 weeks since its final use-up date, all plants will soon be vulnerable to attack.   

“In the autumn, while growing media temperatures remain above 12°C, we recommend applying Vine Weevil Seeka – containing Heterorhabditis bacteriophora nematodes,” says Sam. “Once growing media temperatures dip below 12°C, but remain above 5°C, growers should switch to our cold tolerant Vine Weevil Seeka CT - containing Steinernema kraussei nematodes. To optimise nematode efficacy, we have developed Transporter. A superior blend of surfactants, Transporter optimises water, and hence nematode, distribution in growing media.  

“Customers entering into a contract with ICL have access to meaningful soil temperature data year-round, provided by a network of temperature loggers on UK nurseries,” explains Sam.  “With access to robust, real time temperature data - and supported by our nationwide team of experienced technical area sales managers - growers can optimise control programmes and choose the right species of nematode for the right time of year.” 

Sam is keen to point out that Seeka nematode products are just one component of the Integrated Pest Management (IPM) strategy for vine weevil. “We recommend using these nematode products in a programme with our award-winning Pitcher GR,” he says. “Pitcher GR suppresses the egg and early instar larval stages in containerised crops.”  

To assist in the correct application of these products, ICL has recently launched an online plant health planner. This digital web-based tool is designed to both simplify and optimise plant health programmes on UK nurseries. In line with the Sustainable Use Directive, ICL Plant Health Plans also aim to help growers reduce their reliance on crop protection chemicals by giving the option to choose more sustainable products such as ICL’s Vitalnova biostimulant range.”