Spider mites Predators are still effective on vulnerable crops. Naturalis-L will provide good knock-down control in tunnels and glasshouses with at least 60 per cent humidity. Sequel, Masai, Dynamec and SB Plant Invigorator are useful products at this time of year.
Local Environmental Risk Assessment for Pesticides (LERAP) Products that used to be categorised by an A or B will not have this information on any direct replacements. If an aquatic buffer zone is required, this will be detailed on the label. For example, the new Decis product (MAPP 16124) has a buffer zone of 7m for outdoor amenity vegetation and ornamental crops. The label indicates that for crops with a buffer zone exceeding 5m, the product cannot be applied using handheld equipment. Buffer zones that exceed 5m cannot be reduced in the new LERAP scheme.
Moths Be vigilant for species that attack ornamentals (leopard, swift and tortrix moths, among others). Check vulnerable crops including acer, ash, birch, choisya, Crataegus, euonymus, Malus, oak and prunus. Use a range of pheromone lures attached to Delta traps to identify species for timely spray applications.
Feeding Change to high potash (K) products to harden up soft foliage and green-up pale, older leaves. Use products such as Hortifeeds 2:1:6, Peters Professional Plant Finisher, Sangral 1:1:3, Solufeed 1:0:3, Universol Violet or Vitax 2:1:4.
Rust Control active infections using Amistar (EAMU 2009-0443), Bumper 250EC (EAMUs required), Cuprokylt, Difcor 250EC (EAMUs required), Fandango (EAMU 2009-0226), Folicur, Lyric, Plover (EAMUs required), Signum (EAMU 2012-2141), Thianosan DG or Systhane 20EW.
Wilt diseases Check aster, dianthus, Hebe, penstemon and phlox, especially in glasshouses and tunnels where temperatures can be high even on dull days. Control using Amistar (EAMU 2009-0443), Octave, Signum (EAMU 2012-2141), Switch or T34 Biocontrol (EAMU 2012-1118).
Botrytis Check closely spaced crops with dense, soft foliage. Improve air-flow and control infections with Amistar (EAMU 2009-0443), Octave, Rovral WG (EAMU 2011-3200), Scala (EAMU 2011-1315), Serenade ASO (EAMUs required), Signum (EAMU 2012-2141) or Switch.
John Adlam, Managing director, Dove Associates