Downy mildew diseases, although they tend to be sporadic, can seriously damage hebe, rose and several other major nursery stock and herbaceous perennial species.
Phytophthora ramorum is causing dieback of several nursery stock species in the UK. In Western USA the pathogen is causing the death of some native oaks and other woodland species.
Symptoms of Phytophthora on asparagus were widespread in the UK for the first time in 2002.
Tarsonemid mite (Phytonemus pallidus ssp. fragariae), also known as strawberry mite, is a serious pest of strawberry.