There are no fungicides available to amateur gardeners with activity against downy mildewor grey mould. Prolonged leaf wetness is not required for infection by p owdery mildew, but high humidity is, so providing good air circulation is still important. Avoid drought stress and the overuse of nitrogenous fertilisers. Chemical control Scientific name: Stemphyliumsp., Septoria exotica, Peronospora grisea, Podosphaera fuliginea, Botrytis cinerea

Apply no more than four times per year on roses and ornamentals and no more than six times per year on box trees. How to Use 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 controlEnsure 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. Theproducts above also have recommendations for control of powdery mildew, as do products containing sulphur(Fungus Clear Ultra 2, Mildew Clear for Edibles, Roseclear 3-in-1 action (with fatty acids)). Distorted leaves are often the first sign of infection, especially with the larger-leaved cultivars. A grey/mauve felt-like 'fungal' growth appears on the under-surface of the leaves, with diffuse purple-red or yellow patches developing on the corresponding upper surface. Spray at the first signs of disease and repeat every seven to fourteen days, depending on disease levels.

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. The fungicide tebuconazole with trifloxystrobin (Provanto Fungus Fighter Plus, Toprose Fungus Control & Protect) has a recommendation for the control of leaf spots on ornamental plants. Additionally, the fungicides tebuconazole (Provanto Fungus Fighter Concentrate) and triticonazole (Fungus Clear Ultra) are labelled for the control of other diseases on ornamental plants, and could therefore be used legally on Veronica(at the owner’s risk) to try and control the leaf spotting.Chooseless susceptible cultivars if downy mildew becomes a persistent problem. It is mainly a problem withbroad-leaved cultivarssuch as Veronica‘Midsummer Beauty’ and x ‘Franciscana Variegata’ but also occasionally present in some of the smaller-leavedspecies and cultivars,e.g . V. albicans, V. ‘Frozen Flame’ , V. rakiensis, V . ‘Youngii’ (syn. ‘Carl Teschner’) . Then rinse sprayer thoroughly after use and dispose of washings safely by pouring onto bare soil. Once the bottle is empty, RINSE CONTAINER THOROUGHLY before disposal by manually rinsing three times. This can be done by filling the dosing chamber with clean water, replacing the cap and tipping the water into the bottle. Repeat steps 1 – 4 above to add washings to sprayer at time of filling and dispose of empty container safely. 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. Pour liquid from the dosing chamber into the sprayer and make up to 1 litre with water. Replace cap Pour liquid from the dosing chamber into the sprayer and make up to 1 litre with water. This will treat a lawn area of up to 20m²