Windbreaks: If living windbreaks are trimmed during October make sure that the trimmings are removed and burned as they can be a source of both pest and disease to the crops beside them.
Scale: Control adult scale insects now before the mother sits on top of her eggs and dies. Use Calypso (SOLAs required), Chess WG (2008-2834), Decis, Savona or products containing nicotine. Spraying Oil will penetrate the shell and control the eggs underneath. It will also control adult mites starting to hibernate for the winter. For scale on bay trees consider Majestik or SB Plant Invigorator.
Leatherjackets: Cranefly larvae often cause damage to outdoor conifer and shrub liners. Drench with chlorpyrifos or Intercept 70WG.
What's in store? Check through your chemical store and make sure you have all the older products placed at the front of the shelf. You need to check the MAPP number on the bottle or packet to ensure correct rotation of use. Try to purchase only what you need for a month and re-order as needed to avoid having large quantities of pesticides, which these days can quickly become out of date. Check the dates of any that you are unsure about at www.pesticides.gov.uk and remember that some products may be replaced by one of the same name but with an updated MAPP number.
Phoma: Phoma is a common fungus that is still quite active on a range of nursery stock subjects. It is most commonly identified as a blackening of the stems part way down a shoot and the wilting of that shoot to the tip. It is controlled effectively by Amistar (SOLA 2009-0443), Cercobin WG (SOLA 2008-1384), chlorothalonil, Scotts Octave, Signum (SOLA 2009-1842), Swift SC (SOLA 2008-2882) or Switch. With growth now slowing down it is important, on susceptible species such as Ceanothus, Vinca and Viburnum, to apply before winter dormancy.
Autumn potting: Applying Wiltpruf S600 or Orosorb to plants such as Pieris after potting may help to control the level of transpiration and prevent the brown leaf tips that can develop on the foliage. Warm, sunny days this autumn could cause problems for newly potted stock so keep an eye on these plants, particularly any evergreen species. Make sure that autumn potted plants are in the right places for winter protection to avoid those last-minute changes as soon as frost appears. I find many plants are lost through a lack of planning.
- John Adlam is managing director of Dove Associates.