These diseases are grouped together because they all produce visible moulds, mildews or rusts, which are the fruiting bodies of the attacking fungus. The fungal pathogens causing mildews and rusts are spread mainly by wind and rain, but can also be spread by insects or are seed-borne.

Spots and blights are symptoms of numerous diseases and disorders caused by many factors, - bacteria, fungi, insects, mineral deficiencies, temperature, and occasionally virus. The most common which we deal with here are fungal. (Bacterial spots are covered above under bacteria.)

Club root of brassicas, Leaf curl of peaches, Bladder plum, Silver leaf and Verrucosis

Along with insect pests, fungus diseases are the most common problems in the home garden. Whilst good hygiene, rotational cropping, use of resistant varieties, a healthy compost enriched soil, and balanced fertilising all help, these diseases are still common and in some years can be very devastating.