She quickly attracted attention of the local people, who considered her somewhat eccentric for collecting what they regarded as "useless flowers".

Known in New Guinea pidgin as Long-long Misis bilong plaua (Crazy flower woman), she used this as the title of a brief autobiography, published in 1994.

[2][3][4][5] She and her husband moved to a cocoa plantation close to Lae and in 1956 she became a member of the staff of the Botanic Gardens.

During her time there, she accompanied many collectors on field trips, including to the Jimi Valley and the Kokoda Track.

Away from the highlands, she visited the western part of Papua New Guinea, travelling along the Fly and Strickland rivers to Lake Murray.

[1][3][4][5] Millar later moved to the capital, Port Moresby, to work at the National Botanic Gardens at the University of Papua New Guinea, becoming the curator in 1971, and being known as "Mum".

[2][3] In addition, Millar contributed journal articles, including to the American Orchid Society Bulletin.