Application for ornamentals
This work is part of a larger project being undertaken by RSK ADAS (PO 019d The Bedding and Pot Plant Centre – new product opportunities for bedding and pot plant growers). The component at Silsoe has focused on improving the application of plant protection products (PPPs) for bedding and pot plants through identifying alternative approaches to existing hand-held high-volume systems, which can improve the quantity, uniformity, and distribution of PPPs over plants.
We have been looking at low-cost options, because while we know that the best method of applying pesticides is with an automated spray boom, there are many situations in the UK where this is not appropriate, or not cost-effective, and frequently both. There are well-known problems with existing approaches using spray pistols, but it is difficult to find better alternatives.
We conducted experiments on pelargonium and pansy, and showed that reducing the applied volume from 1000 L/ha or more down to around 500 L/ha has the potential to improve efficacy as well as reducing losses.
The easiest way to do this with existing equipment is to replace the nozzle with one of a lower flow rate. Also, if there is the potential to increase the speed of spraying - perhaps by walking faster, this can contribute to faster workrates and reduced labour costs.
We looked at one example of an electric air-assisted knapsack sprayer, which applied at very low volumes (< 250 L/ha). This performed better than expected, but gave no advantages and some potential disadvantages.