T. Newton Cook, 70, a retired federal housing official and a noted gardener, died Sept. 1 at Doctor's Hospital in Washington. He had a heart ailment.

Mr. Cook was born on a farm near Boone, N.C. He graduated from North Carolina State University in 1931 with a degree in agricultural economics and then joined the bureau of land management and reclamation in the U.S. Department of Agriculture in North Carolina. He later became a federal housing official and worked in Atlanta and in Richmond and Norfolk.

In 1955, he moved to the Washington area and became a family housing official for the Department of the Navy. He later transferred to the Department of the Air Force, where he continued this work until his retirement in 1973.

Mr. Cook also was a certified judge of fruits, vegetables and flowers of the National Association of Garden Clubs. He held the patents on five kinds of gladioluses he had developed, including a yellow variety called "Carolina Moon." Gardening was a principal occupation during his retirement.

Survivors include his wife, Josephine Coman Cook, of the home in Falls Church; a brother, Carl C., of Ferndale, Mich., and a sister, Mrs. William E. Lovelace, of Arlington.

The family suggests that expressions of sympathy be in the form of contributions to the American Heart Association.