Diseased herbs are a Farming plant that appears after a growing herb in a herb patch becomes diseased. There are 3 possible stages when herbs can become diseased, and all herbs share the same model for the diseased versions. Disease can be restored to the healthy growing stage by using a plant cure on the herb, or by casting Cure Plant from the Lunar spellbook. If the herbs are left diseased for too long, they will become dead herbs.
The herbs can be inspected to determine which type of herb had been planted.