Western flower thrip: Add thrip pheromone lures to blue sticky traps to encourage adults and nymphs out from flowers and growing tips. Replace your traps and lures every three weeks.
Phoma: Tip dieback caused by a Phoma infection on Ceanothus and Viburnum is still present. Check for tip death of shoots and spray with Scotts Octave or Serenade ASO (SOLA 2009-0246) if you use biological control for spider mites.
Rose black spot: Make sure your protectant sprays are up to date, particularly in unsettled weather. If you find the disease now on foliage outdoors, spray with Systhane 20EW or Lyric followed by Folicur.
Escallonia: Avoid yellowing of lower foliage, which is common on these plants in July and August, by using a magnesium chelate. These liquid feed formulations can be added to most pesticide sprays as a tank mix. You can also use Epsom salts (magnesium sulphate), applied at the rate of 20 grams per litre of water as a foliar spray to run-off.
Tortrix moths: Toppel 100EC or Decis (non-IPM) are very effective and provide persistent control on caterpillars for around 10 days. Include Conserve, Dimilin Flo, Insegar WG, Majestik, Nemolt (SOLA 2007-2120) and Runner (SOLA 2008-2903) in your ornamentals control programme - these products are generally predator-friendly. Use Dipel DF on herbs (SOLAs required). Add a wetting agent to get good penetration of the leaf rolls. Identify the species by first installing the full range of pheromone traps available.
Chrysanthemum white rust: This disease shows up as whitish pustules on the underside of the leaf and yellow blotches on the top side. Aim to keep leaves dry by growing on sand beds or capillary matting to reduce its incidence. Consider using Amistar (SOLA 2001-1684) with a high water rate, spraying to run-off - alternate with Bumper 250EC (SOLA 2009-0707) to avoid disease resistance.
Powdery mildew: Keep spraying vulnerable species including Acanthus, Acer, Aquilegia, Aster, Crataegus, Euonymus, Euphorbia, Fagus, hops, Hydrangea, Lonicera, lupins, Milium, oaks, Phlox, roses and Verbena. Dry up fungal growth with food-grade potassium bicarbonate.
Biobeds: Consider installing a lined biobed using your Waste Regulations exemption 16. It must be sited at least 10m from a watercourse and 50m from a spring, well or borehole.
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