Those that die from the tip downwards are suffering from Botrytis and need an Amistar (SOLA 2009-0443), Rovral WG, Scotts Octave, Serenade ASO (SOLA 2009-0246) or a Switch spray.
Downy mildew: Initiate controls on Buddleja, Digitalis, Geum, Hebe, Osteospermum, pansy, rose and other susceptible herbaceous perennials as the disease begins to show. Use Aliette 80WG, Fubol Gold WG (SOLA required), Filex/Proplant, Signum (SOLA 2009-1842) or Subdue if the leaves show the tell-tale yellowing on the top surface and angular darker patterns. Add a wetting agent for under-leaf coverage.
Pre-planting operations: Prepare land for new plantings at least a week before planting and leave for weed seedlings to emerge. Burn them off with a contact herbicide a day before planting to reduce the weed population and give your residual herbicide a far better chance of control.
Root rotting: Prevent disease spreading on seedling material with Aliette 80WG, Basilex, Cuprokylt FL, Filex/Proplant, Serenade ASO (SOLA 2009-0246) or Subdue. Make sure moisture levels and air temperatures are not too high and adequate ventilation is available to reduce the need for pesticide applications. Use predators or nematodes to control sciarid fly larva and reduce damage to newly-emerging roots.
Aphids: Check herbaceous perennials, bedding and primulas. Identify the aphid species to introduce the correct predator or spray with Agri-50E, Aphox, Chess WG (SOLA 2008-2834), Majestik, Naturalis-L or SB Plant Invigorator. Keep inspecting conifers - early aphid infestations can cause extensive needle drop in April/May. Control by contact products needs good coverage, so ensure high water rates, add a wetting agent and aim sprays directly into the plant canopy.
White fleece: Keep fleece near vulnerable crops with the continued risk of sudden cold snaps and damaging frosts.
Revocations: Check the Chemicals Regulation Directorate website (www.pesticides.gov.uk) for product withdrawals on a regular basis. Products containing propachlor and dichlobenil have been revoked from storage and use from 18 March. Applaud will be similarly revoked on 30 March.
John Adlam is managing director at Dove Associates
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