In the early years, Plantinga primarily concentrated on his own type of so-called
Beerenburg, a local drink that became especially popular due to it being considered a good cure against flu and the
common cold. Locally, this beverage became known as "a little KP" (Dutch "een KP-tje"). On 29 September 1900 his son Gerrit Herman (January 9, 1876 – November 30, 1962) joined Klaas Plantinga in the distillery. The company name then became "K. Plantinga & Zoon, Distilleerderij 2e Klasse" ("K. Plantinga & Son, distillery 2nd class"). On 8 October 1910 another of Klaas' sons, Sicco, joined. At that time Klaas himself retired. The company diversified into importing a variety of wines and spirits, as well as producing some themselves. Gerrit Herman's second son, Louwrens Baltus (October 5, 1902 – June 2, 1993) joined the company on 14 July 1920. He had studied in
Berlin. He started sales outside of the Bolsward region. Louwrens Baltus, incidentally, is the man whose signature is on practically all Plantinga products, including
Plantiac Vieux (though not, notably, on Plantinga Beerenburg). Klaas Plantinga died on July 17, 1922. His wife, Ytje, had already died on March 3, 1922. ==Geography==