Alcea "Alcea" species are used as food plants by the larvae of some Lepidoptera species including "Bucculatrix quadrigemina" and "Vanessa cardui", the painted lady. The mallow flea beetle ("Podagrica fuscicornis") is a pest that makes tiny holes in the leaves. Cutworms, aphids, and capsid bugs use the plant as a food source in hotter and drier conditions. A number of weevils use "A. rosea" as their host plant, including "Rhopalapion longirostre", "Alocentron curvirostre", and "Aspidapion validum". The plants are also susceptible to the pathogenic fungus "Puccinia malvacearum", the hollyhock rust. A hollyhock flower, known in Japan as , was incorporated into
Clonostachys rosea f. rosea Clonostachys rosea f. rosea Clonostachys rosea f. rosea, also known as Gliocladium roseum, is a species of fungus in the family Bionectriaceae. It colonizes living plants as an endophyte, digests material in soil as a saprophyte and is also known as a parasite of other fungi and of nematodes. It produces a wide range of volatile organic compounds which are toxic to organisms including other fungi, bacteria, and insects, and is of interest as a biological pest control agent. "Clonostachys rosea" protects plants against "Botrytis cinerea" ("grey mold") by suppressing spore production. Its hyphae have been found to coil around,