The term perulas, in botany, means a leaf modified in order to provide protection to the buds of plants.
Perulas are squamiform leaves that protect embryonic buds and that typically fall when the buds hatch.
These organs, typical of fanerophytes, which present buds more than 30 cm above the ground.
In these species the dormant buds, which suspend their growth for prolonged periods, such as during the cold winter seasons, are protected by their outer leathery leaves and often covered by sticky substances or hairs, which are precisely the perulas.
At the end of the quiescent season, in the spring, (for example with the arrival of spring) the perulas open and fall, leaving scars on the axis of the gem at their insertion point and allowing the development of the gem itself, which it can therefore give rise to a sprout.
The pearls are very present in areas with a warm temperate climate and with good water availability.