A nursery in Kesswil was founded by Willy Roth sen. (b. 1895) in 1921. His son Konrad Roth (b. 1925) established in 1951 with his wife Maria Roth-Patzen a separate company. This was taken over by Zulauf AG in 1983, however, is managed separately.
[From
Rosa Helvetica, 1986, p. 42-43:] Konrad Roth established 1951 in Kesswil (Canton Thurgau) his own company, which also took up growing roses...