He also collected plants in Egypt and Sudan that now form part of the herbarium of the National Botanic Garden of Belgium.
He took a keen interest in flower gardening, and was responsible for three important publications of the firm: Les Fleurs de Pleine Terre, Le Manuel de Floriculture, and the Hortus Vilmorinianus.
During World War I, as a reserve officer in the French Army, Vilmorin was for a time attached to the Anglo-Indian Army in France as an interpreter, and later was a French Purchasing Agent in London.
[1] Philippe Vilmorin married Mélanie Gaufridy de Dortan; they raised six children: Philippe de Vilmorin died on 29 June 1917 aged 45.
He had been ill in southern France for some months, exhausted by his missions between Paris and London.