Really depends on what you’re using for a medium. Are you in soil? If so, what brand? Some soils you can get 20-40 days of growth before feeding nutrients. If you tell us what medium you’re using, we can give you more details.
Are you close to harvest? Can you post a pic of the whole plant? If it’s close to harvest and you’re seeing decaying leaves, it’s probably nothing to panic about.
Great job!!! Would you be willing to take some photos right before harvest so I can see? Some individual bud pics would be fantastic. They look so good!