[1] He is notable for the introduction of cassava plants (from the island of Bantam, near Sumatra) as a food source to alleviate famines in the then Dutch East Indies.
[2] Together with his collaborator Justus Carl Hasskarl, he introduced the cultivation of Cinchona trees (from Peru) for the production of quinine to treat malaria (ca.
There was a bitter conflict between Teijsmann and two fellow botanists, Johann Eliza de Vrij (1813–1898) and Franz Wilhelm Junghuhn on the effectiveness of various Cinchona species in the treatment of malaria.
Nevertheless, successful experimentation on the plant was carried out in the new Cibodas Gardens which eventually made Java the largest producer of kina (Cinchona bark).
[6] The genus Teysmannia (since the work of Harold Emery Moore more correctly called Johannesteijsmannia) is named in his honour, together with several plant species.