Leaf Spot can affect a wide range of ornamental garden plants being present as either bacterial or fungal leaf spot Bacterial leaf spot - circular or angular necrotic (dead) patches on the foliage. Bacterial leaf spots are surrounded by a bright yellow 'halo'. There are no raised spots on the leaves associated to bacterial leaf spot. Bacteria usually spread by rain or water splash from leaf to leaf. This leaf spotting is not usually a problem but may indicate other underlying plant problems.
Fungal Leaf Spots - These spots may merge causing large areas of the leaf to die. Although not considered a problem it can indicate other underlying plant problems.
Cultural control: Remove affected leaves if necessary, rake up and dispose of fallen leaves at the end of the season to minimise infection being carried over/over-wintered.
Product Solution: Systhane Fungus Fighter, Fungus Fighter Disease Control, Multirose Concentrate 2, Fruit and Vegetable Disease Control.