From the Wikipedia link above:
"Although all-electronic color was introduced in the U.S. in 1953,[2] high prices and the scarcity of color programming greatly slowed its acceptance in the marketplace. The first national color broadcast (the 1954 Tournament of Roses Parade) occurred on January 1, 1954, but over the next dozen years most network broadcasts, and nearly all local programming, continued to be in black-and-white. In 1956 NBC's The Perry Como Show became the first live network television series to present a majority of episodes in color. CBS's The Big Record, starring pop vocalist Patti Page, was the first television show broadcast in color for the entire 1957-1958 season; its production costs were greater than most movies were at the time not only because of all the stars featured on the hour-long extravaganza but the extreme high intensity lighting and electronics required for the new RCA TK-41 cameras. It was not until the mid-1960s that color sets started selling in large numbers, due in part to the color transition of 1965 in which it was announced that over half of all network prime-time programming would be broadcast in color that autumn. The first all-color prime-time season came just one year later."
