During the World War II, Ku became the first Asian-American reporter for the Associated Press and was the first Asian-American female writer for the Honolulu Star-Bulletin. She later worked as a public information specialist for the Department of Education, retiring in 1975.

That same year, she took over as executive director of the Honolulu Community Media Council, serving in the position for 25 years. The volunteer media council was established in 1970 to improve public access to information, strengthen public support for First Amendment freedoms, and promote accurate and fair journalism in Hawai'i.

In 2002, Ku was honored with the group's Fletcher Knebel Award for outstanding contributions to journalism.

She was born April 24, 1910, in Kailua. She was one of 15 children, and grew up on the 'Ewa Plantation, where her father worked as a luna. After attending Mid-Pacific Institute on a scholarship, she studied at the University of Hawai'i and later at the University of Missouri School of Journalism.