Heathers Ericas and callunas can suffer from Rhizoctonia now, particularly protected crops and young overwintering plugs.
Those where no control programme is in place are often most at risk. Control with Rovral WG or Switch.
Rabbits Using gas tablets such as Talunex during the winter months when populations are small and no young are present is also effective on any rabbit holes that have been established within the container area. Ensure that your staff are suitably trained and certificated to carry out the gassing work.
Heaters If you are using direct-fired heaters at the moment, remember that you should use paraffin with low sulphur content. Glasshouses or polytunnels shut up for extended periods need their doors or vents opened at least once a day for a short time to provide a change in air. This reduces the risk of foliar damage from sulphur fumes from paraffin or ethylene from gas.
Land preparations This process can make a major difference to the ease of planting and lifting, and contribute greatly to the growth of plants. Keep tractor movements to a minimum to avoid compaction and maintain levels of humus in mineral soils by introducing green manure crops into a crop rotation.
Insect controls Apply Certis Spraying Oil to dormant crops to control spider mites, mealy bug and scale insects. Avoid spraying before or after frost to prevent foliar damage.
Winter injury Watch for waterlogging, drought from unavailable water from frozen compost, physical damage, wind chill and wind scorch. Applying anti-transpirants helps to prevent water loss in plants in these situations. Make sure that vulnerable crops, including spring-flowering species, are suitably protected from strong winds by windbreaks, Cosytex or fleece. Plants that are pot-thick will have better root protection because less pot surface is exposed.
Twin-skinned tunnels The added value of having twin-skinned tunnels will show through when we start to heat crops. When you re-clad in the warmer months, think about having a twin-skin cover - the heating cost saving can be up to 45 per cent compared to a tunnel with a single skin.
John Adlam, Managing director, Dove Associates