There are several cultivars of kava, with varying concentrations of primary and secondary psychoactive substances.
The largest number are grown in the Republic of Vanuatu, and so it is recognised as the "home" of kava. Kava was historically grown in Hawaii, Polynesia, Micronesia, Vanuatu, Fiji, the Samoas and Tonga. Some is grown recently in the Solomon Islands. Kava is an export cash crop in Vanuatu, Fiji and Tonga.
The kava shrub thrives in loose, well-drained soils where plenty of air reaches the roots. It grows naturally where rainfall is plentiful (over 2,000 mm/yr). Ideal growing conditions are 21–35 °C and over 70% relative humidity. Too much sunlight is harmful, especially in early growth, so kava is an understory crop.
Kava cannot reproduce sexually. Its cultivation is entirely by propagation from stem cuttings.
Plants are harvested after a minimum of 4 years of age, when the concentrations of kavalactones reaches its peak. After reaching about 2 m height, plants grow a wider stalk and additional stalks, but not much taller. The roots can reach a depth of 60 cm.