Warehousing a cash crop allows control over the supply of goods, and therefore greater profits as the vagaries of market prices have less effect.
By holding onto a crop until a market is “right”, plantation owners can get the best price for their harvest. They can also calm the volatility of the commodity’s market by evening out the supply over the course of a year, rather than having a harvest glut and then a shortage for the rest of the time. A warehouse also allows plantation owners to wait until the season and winds are favourable for a fast sea journey back to the homeland; shipping losses and transit times are both reduced. Finally, Warehousing also allows smaller crops to be consolidating for shipping back to the home market, and for the crop to be properly graded. The finest parts of the harvest can be sold at the highest price, rather than simply being lumped in with any old dross.