Biological control The Sustainable Use Directive encourages using an IPM approach to control pests, diseases and weeds. For pests on protected crops, use products with short persistence such as Aphox, Majestik, SB Plant Invigorator, Spruzit or Pyrethrum 5EC before introducing predators.
Bees Check product labels for specific information and only apply when bees are not foraging - early morning or late evening depending on weather. Notify local beekeepers if spraying flowering crops.
Leaf-curling aphids Control on ornamental cherries and other plants such as Viburnum carcephalum with Calypso (EAMUs required), Chess WG (EAMU 2013-2016), Gazelle SG or Movento (EAMU 2011-1987), which will provide good control even if pests have distorted the foliage.
Western flower thrips Control scratching or flecking on leaves and flowers with Conserve, Dynamec or Naturalis-L. Apply Amblyseius cucumeris to foliage for adult and nymph control and Atheta coriaria, Macrocheles robustulus and Steinernema feltiae to composts to control pupae. Use blue sticky traps to monitor populations.
Caterpillars Install pheromone lures (in Delta traps) over vulnerable protected crops to identify damaging species. Control pests on outdoor Betula, Crataegus and Carpinus using Decis, Dimilin Flo, Insegar WG, Runner (EAMU 2012-0448), Explicit (EAMU 2011-2090), Toppel 100 (EAMU 2013-2410) or Tracer (EAMU 2008-2908).
Aphids Apply Aphox, Chess WG (EAMU 2013-2016), Majestik, Movento (EAMU 2011-1987), Naturalis-L, Pyrethrum 5EC, Savona, SB Plant Invigorator or Spruzit. Non-IPM products include Calypso (EAMUs required), Decis, Gazelle SG or Hallmark WZT (EAMU 2008-2944).
Leafhopper Check chrysanthemum, Lamium, Mentha, nepeta, rhododendron and salvia for flecking damage from feeding. Control using Chess WG (EAMU 2013-2016), Gazelle SG, Majestik or SB Plant Invigorator. Herb crops require specific EAMUs. Complete the harvest intervals before despatch.
John Adlam, Managing director, Dove Associates, HorticultureWeek.co.uk/nursery