Herman Seifert was the eldest of the seven Seifert brothers, six of whom were prominent in the flax-milling industry of Manawatu. Herman was a flax-miller in Southland until 1909, when he moved to Manawatu and was associated with the "Weka" mill at Shannon and the "Rangitāne" mill at Rangitāne (Opiki). He then became Chairman of Directors of the Tane Hemp Company Limited, which ran the flour-stripper "Tane" mill at Rangitane (Opiki). During the 1930s he was also associated with flax-milling ventures at Paiaka (near Foxton) and Australia.