White berries are used in Herblore to make super defence potions, and regular defence potions. They are also used in The Hand in the Sand quest, as well as Mourning’s Ends Part II, where it’s part of a list containing 50 different items in order to get a Death talisman.
Filling a compost bin with 15 white berries will yield 15 buckets of supercompost. However, this is not recommended as watermelons are far cheaper and have the same effect.
While planting the seed requires level 59 Farming, picking the berries does not. Once all berries are picked from the bush, it will produce more berries, approximately 1 per 25 minutes; one seed can produce a minimum of 4 berries, where the Farming level reduces the chance of using up one of the three “lives” of the patch, much like harvesting herb patches.
You can grow White berries in the following locations: