Spraying Frost-free, protected nursery stock can still be sprayed with Rovral WG (EAMU 2011-3200) or Switch during the winter period as a precautionary disease control, especially for Botrytis. Add in a wetting agent for plants with hairy foliage — use an air-assisted sprayer if possible to get good penetration. Focus applications on Helleborus, Cordyline, lavenders, phormiums and yucca. Apply in the morning to allow foliage time to dry off.
Product choice Do not use systemic products at this time of year when plants are dormant. The number of applications available either per crop or per year are already restricted for many systemic products and should only be made during the growing season.
Spray programmes Include biopesticides into your programme including AQ10, Botanigard WP, DiPel DF, Naturalis-L, Prestop, Serenade ASO and T34 Biocontrol. Most of these have ornamentals EAMUs. Understand their humidity and temperature requirements to ensure that they are used to their maximum effect — these products will work well in your integrated pest management plan. Supplier information (particularly EIS sheets) provides useful data on product safety with predators and non-target organisms.
Growing media Check the conductivity of composts that have been stored for a period of time to avoid root damage at potting next season and to ensure that they will provide a good flush of growth after potting. High conductivity levels indicate that the controlled-release fertiliser prills have been
Vent gear Grease up all vent gear — motors, racks and bearings can get damaged during the busy summer months through lack of maintenance. Health & Safety Executive leaflet AIS12 provides good safety advice for glasshouse work.
Weeds Butisan S, Devrinol, Flexidor, Sumimax (EAMU 2008-2881), Springbok (EAMUs required), Wing-P (EAMU 2013-0253) and Venzar Flowable can be applied now to control weed infestations on compost surfaces. Check label and off-label information to see whether products are approved for use
on protected crops.
Pests Clean up residual pests using broad-spectrum products such as Decis (EAMU 2014-1011) and Hallmark WZT (EAMU 2008-2944) where predator applications have ended. Where predators are still active, use Majestik, Pyrethrum 5EC, Spruzit or SB Plant Invigorator instead. Control slugs and snails using pellets containing ferric phosphate.
John Adlam, managing director, Dove Associates