Spray directly onto the plant making sure a good coverage is applied to both upper and lower leaf surface.

Downy mildew: the downy mildew pathogen survives over winter as resting spores in dead, infected leaves. These initiate new infections in the spring. Subsequent infections occur from airborne spores produced on these initial infections. Wet conditions are required for infection to occur and the disease is very seldom seen on vines grown under glass. The pathogen is an obligate biotroph (it feeds on the living cells for extended periods without killing them, and cannot live on dead plant material). Vitis vinifera is susceptible; other Vitis spp. and related Parthenocissus spp. (Boston ivy, Virginia creeper) and Ampelopsis are less affected. Prune shrubs to give an open structure (which will again improve air circulation and reduce humidity) Asexual spores (conidia) of the g rey mouldfungus are always present in the air. They require leaf wetness or very high humidity to germinate and infect. Damaged or senescent plant parts are a very common way in which the fungus gains entry to the plant. The disease has a huge host range, and is active over a wide temperature range. Most powdery mildew fungi have a host range restricted to a relatively few, related plants, but these can include wild relatives which can be sources of infection, e.g. wild crab apples may be sources of infection for apple orchards. Badly affected shoots are best prunedout and disposed of as soon as the symptoms are seen. During routine spring pruning any shoots showing large patches of mildew around the thorns should also be cut outAs with other powdery mildews, these species grow initially over the leaf surface, feeding from the tissues but not killing them, and producingairborne spores which spread infection.Later the tissues die and, unusually for powdery mildew infection, drop out leaving holes and tattered edges to the leaves. An overwintering stage is of minor importance, most survival through the winter is as mycelium on the evergreen leaves. Don’t plant too densely, giving space between plants. Aim for an open environment to increase air circulation and reduce humidity The RHS believes that avoiding pests, diseases and weeds by good practice in cultivation methods, cultivarselection, garden hygiene and encouraging or introducing natural enemies, should be the first line of control. If chemical controls are used, they should be used only in a minimal and highly targeted manner. Non-chemical control Under certain environmental conditions some Stemphylium speciesare thought to be able to produce a sexual stage, and spores liberated from the fruiting bodies of the fungus in this scenario could account for the overwintering survival of the fungus and its long distance dissemination.

Use all year round, indoors and out. When applied on edibles there is no harvest interval – just wash before eating. Growing Success Disease & Funghus should be used preventatively or at first sign of infestation. Mildew Clear for Edibles (sulphur) carriesa label recommendation for the control of gooseberry mildew. None of the products in the lists above are likely to have any activity against bacterial shothole. Avoid overhead watering as this increases humidity around the foliage, which makes the plants more prone to powdery and downy mildewsThe RHS believes that avoiding pests, diseases and weeds by good practice in cultivation methods, cultivar selection, garden hygiene and encouraging or introducing natural enemies, should be the first line of control. If chemical controls are used, they should be used only in a minimal and highly targeted manner. Non-chemical control Ensure that any leaves falling prematurely from an infected plant are collected up and disposed of (by burning, burial or consigning to the council green waste). Heavily-infected shoots could be trimmed off and disposed of in the same way.