How much Lichen may grow per year?

Lichen growth rates can vary significantly depending on species, environmental conditions, and habitat. On average, lichen may grow anywhere from 1 to 5 millimeters per year. In some optimal conditions, certain species can grow up to 10 millimeters annually, while in harsher environments, growth may be considerably slower. Factors such as moisture, light, and temperature play crucial roles in their growth rates.