For some, the Rose Parade is a 365-day occupation

For millions of Americans, it's a once-a-year tradition: flicking on the TV set New Year's Day and settling down for two hours of one of the country's most elaborate events, the Tournament of Roses Parade.

For the six companies who design, build, and decorate the 60 flower-packed floats, however, the Tournament of Roses is more than an annual event. It's a year-long business -- a business that no doubt has its quiet moments, but which barrels its way at a pell-mell pace in late December each year as workers rush to glue millions of flowers into place in time for the Jan. 1 gala.

Here at C. E. Bent & Son, for example, the oldest and largest of the six firms in and around Pasadena, scores of young volunteer workers scramble about a huge warehouse filled with half-covered floats, ladders, boxes of chrysanthemums (mums for short) and marigolds, buckets of gladiolas and irises, and bundles of baby's breath. Under the supervision of Bent employees, they cut here and glue there -- work that continues almost around-the-clock until just hours before the Rose Parade begins.

''We're in really good shape this year,'' says Janice Bent, a stockbroker who still finds time to help with her father's business each year. ''Last year, or the year before, a lot of the crews that had promised to come didn't show up. We called up all the local rock stations, and asked them to ask the kids to come down.''

This year, she says, some 3,000 volunteers will help the Bents glue hundreds of thousands of flowers (including a quarter of a million roses), seeds, and bark bits on the 24 floats that the family's two companies were contracted to build for this year's event, the tournament's 93rd parade. (The Bent's year-round staff numbers only 10 employees. Like other floatbuilders, they depend on community volunteers to help decorate the floats).

Typically, work on a float begins with the announcement in February of a parade theme for the following January - 1982's theme is ''Friends and Neighbors.'' Designs for interested parade entrants are drawn up first in pencil , then in watercolor renditions when a final design is chosen. Elaboration of detail depends on how much a client wants to spend - with prices ranging from $ 25,000 to more than $100,000 per float. (''Twenty thousand,'' jokes one insider, ''will get you a guy walking down the road holding a bunch of mums in his hand.'')

Float bodies are built on a stripped-down automobile or truck chassis, and covered with metal or wood frames, chicken wire, and a special polyvinyl spray. According to tournament rules, every inch of the float -- which cannot be larger than 16 feet high, 18 feet wide, and 50 feet long -- must be covered with natural materials such as flowers, barks, and leaves. Among the materials used are eggplant skins (for purple coloring), tangerine skins (for claws), hyacinth root and onion seeds (for black coloring), as well as orchids, chrysanthemums, carnations, and, of course, roses.

The parade dates back to 1890, when the tournament's founding fathers told Pasadena citizens to ''Go home and pick your natural flowers and turn them into displays'' for the first parade of horse-drawn buggies and carriages.