Ruku was born in Raetihi the daughter of Te Reimana Tuatini of Ngāti Uenuku of Te Ati Haunui-a-Pāpārangi from the Whanganui River and Mekura Teone-Wiwi of Ngāti Hauiti, Tuwharetoa, Ngāi Tahu-Ngāti Māmoe, Te Ruahikihiki. She was raised on a dairy farm in Raetihi and was educated at Raetihi Primary School. After leaving school she helped on the family farm after the death of her father. She married Te Rangimarie Arahanga of Tuwharetoa, Uenuke, Te Ati-Haunui-a-Papaerangi and they had six children. She was an active member of the Māori Women’s Welfare League.
- Interview with Ruku Arahanga on 6 Apr. 1993.
- "‘The Food Basket of Rakaihautu’: Taumutu." The Past Today: Historic Places in New Zealand. Ed. John Wilson. Auckland, N.Z.: Historic Places Trust, Pacific Publishers, 1987. 68-75. Rpt. in two parts in Tu Tangata 35 (Apr./May 1987): 28-30 and in Tu Tangata 36 (June/July 1987): 46-48.
- In this account of Taumutu, the writer recalls the former abundance of fish in Te Waihora (Lake Ellesmere), provides a tribal history of the area, and discusses the impact of European settlement and the contribution of H.K.Taiaroa, and examines the significant buildings and archaeological sites in the district.
- "Awhitu House at 100 Years." John Wilson. Te Karanga: Canterbury Māori Studies Association 4.3 (Nov 1988): 6-10.
- John Wilson states that he wrote this article with Riki Ellison, Ruku Arahanga, Ruruhira and Jim Williams for publication in The Press in 1982 when the centenary celebrations of Awhitu House were being held. Biographical notes of Ngāi Tahu chief Te Matenga Taiaroa and his son Hori Kerei Taiaroa are provided, and Wilson discusses the building of Te Awhitu House, its various inhabitants and its significance in the Taumutu district.
- "Riki Te Mairaki Taiaroa: An Interview With Ruku Arahanga." John Wilson. Te Karanga: Canterbury Māori Studies Association 4.3 (Nov. 1988): 26-35.
- This article is composed of sections of an interview between John Wilson and Ruku Arahanga in November 1988 in which Ruku recalls her memories of her great uncle, ‘Poua Dick’, Riki Te Mairaki Taiaroa, (1866-1954).
- "Ruku Arahanga." Te Timatanga Tātau Tātau: Early Stories from Founding Members of the Māori Women’s Welfare League. As told to Dame Mira Szaszy. Ed. Anna Rogers and Maria Simpson (Wāhanga Māori) Photographs by Margaret Kāwharu. Wellington, N.Z.: Māori Women’s Welfare League - Bridget Williams, 1993. 2-9.
- In this interview on 3 March 1990, Ruku Arahanga tells Mira Szaszy of her whakapapa, her upbringing on a dairy farm in Raetihi, her association with Ngāti Poneke in the 1940s and her marriage to Te Rangi-Marie Arahanga and the raising of their six children. She also describes her involvement with the Health League and later with the Māori Women’s Welfare League in Raetihi and in Taumutu.
- "Ruku Arahanga." Te Karanga: Canterbury Māori Studies Association 4.3 (Nov. 1988): 42.
- A short tribute to Ruku Arahanga when she was presented with Life Membership of the Canterbury Māori Studies Association.
- Erai, Michelle, Fuli, Everdina, Irwin, Kathie and Wilcox, Lenaire. Māori Women: An Annotated Bibliography. [Wellington, N.Z.]: Michelle Erai, Everdina Fuli, Kathie Irwin and Lenaire Wilcox, 1991. 1.