BOVEDA HUMIDITITY PACK is ideal to keep your plant material fresh.  Thanks to BOVEDA's revolutionary technology, the relative moisture always remains at a maximum of 58%

Due to the gely consistency, Boveda dries out very slowly.
If Boveda is no longer gel -like, but is hard it is used up and needs to be renewed. The durability is strongly influenced by the size of the storage box/humidor, the amount of the freshness to be kept as well as the ambient moisture and temperature. 

Depending on the location, the durability is from a few weeks to almost a year.