Staying in control
Peter considers how ways of controlling greenfly and other insect pests have changed
MY first job as a 16 year old was working as a nursery hand at Cramphorn’s Seed Trial Grounds in Essex. When winter weather prevented outdoor work we were employed in the seed packing warehouse filling small cardboard cartons with 20% DDT and other insecticidal dusts.
Emptying large paper bags of these powders into the dispensing hopper filled the air with white dust and sent us home
“Tobacco is after all a product of nature”
looking like the Camberwick Green TV character ‘Windy Miller’! What health and safety officers would make of that today and the use of lead arsenate as codlin moth control in orchards I dread to think.
Back then greenfly, other coloured aphis and greenhouse pests were controlled under glass by burning small heaps of nicotine shreds down the path. The move to more specific man made plant pest control materials was welcomed, especially ‘Rapid’ (pirimicarb), which killed aphids while leaving the beneficial insects and pollinators unharmed.
I find it difficult to understand why we can still smoke and inhale nicotine from tobacco and yet are unable to use it for pest control. It is, after all, a product of nature as are the still acceptable pyrethrum extracts. And while soft soaps and oils are now deemed safer insecticides, they are not as specific as ‘Rapid’, which is no longer available to gardeners. Using oils as a greenfly control on lilies has an extra benefit however because, as the aphids go to push their feeding parts into the leaf, the oil coating wipes off virus disease widely spread by this pest.
Personally I prefer to use modern systemic insecticides with precision and at the right time to control greenfly and other pests. Applied either at the very early stage of growth, well before flowering, or after flowering to reduce the risk of harming beneficial insects.