Kola Nut

Kola nut trees favor a hot, humid tropical rainforest climate but tolerate a dry season where groundwater is accessible, and they have been found growing above 300 meters on deep, rich soils under heavy, evenly distributed rainfall. Growers keep the ground weeded by hand or with herbicide, and any irrigation must be matched with effective drainage since excess water harms the plant. Trees grown without adequate shade respond well to fertilizer, and windbreaks are commonly provided to protect them from strong gales. Seedlings are typically started in containers and transplanted outside once germinated, though the trees can take a decade before bearing nuts.

The kola weevil Balanogastris kolae attacks the nuts, and the moth Characoma strictigrapta, which also troubles cacao, produces larvae that bore into them. Traders sometimes treat nursery plants with an extract of Rauvolfia vomitoria bark or pulverized Xylopia and Capsicum fruit to counter these attacks. The cacao pests of the genus Sahlbergella have also been found on kola trees, using them as an alternative host, while the seeds are liable to worm attack and the wood itself is vulnerable to borer damage.

Kola nuts are gathered mechanically or by hand, plucked directly from the branches, then hand-collected and dried in the sun for commercial sale. Once dried, they can be kept for a long time if stored somewhere cool and dry.

West Africans chew kola nuts fresh as a central nervous system stimulant, in both everyday and ceremonial settings, presenting plates of them to chiefs and visiting guests as a gesture of hospitality. The nuts have also been planted on graves as part of ritual practice, and laborers in various regions chew them to stave off fatigue and hunger. In Brazil and the West Indies people use kola as a folk remedy for hangover, intoxication, and diarrhea, while elsewhere the ground nut mixed with honey is taken to aid digestion and ease coughs. Historically the nut supplied both flavor and caffeine to early cola soft drinks, though major commercial brands no longer use kola extract.