(Reuters) - Country singer and songwriter Slim Whitman, known for his smooth falsetto and yodeling talent, died in Florida on Wednesday at the age of 90, his son-in-law said.

"He died last night at the Orange Park hospital at about 12.45 this morning of heart failure," Roy Beagle told Reuters. "We had a 90th birthday party for him in January and he looked good, but he had been in failing health since then."

Born Ottis Dewey Whitman Jr., he was self-taught on the guitar and had a string of hits such as "Rose Marie", "Indian Love Call" and "Secret Love". Whitman recorded dozens of albums and sold millions of records during his career, which began in the late 1940.

(Reporting by Patricia Reaney; editing by Gunna Dickson)