411 REFERENCE · Wikibooks
Horticulture/Excluding Plant Pathogens
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
The best way to control plant diseases is to simply exclude the pathogen from the garden. While this is often impossible because many diseases are wind-borne, putting some effort into exclusion is worth the time.
One way to exclude pathogens is to "quarantine" any new plants for a wile before planting them in the garden. This is especially important for some of the more serious soil-borne fungi such as Phytophthora, Verticillium, and Sclerotinia.
Removing alternate hosts is effective for many pathogens.
Controlling vectors is important for many diseases.