They evolved from flower-decorated horse carriages with the present day requirement that "every inch of every float must be covered with flowers or other natural materials, such as leaves, seeds or bark".
The first parade known as the “Battle of Flowers”[2] was initiated by naturalist and teacher of zoology, Charles Frederick Holder, who was the first to introduce the idea of the Tournament of Roses to the Valley Hunt Club.
[3] The Valley Hunt Club was made up of wealthy Pasadena residents who migrated from the Eastern and Midwestern states.
Since many residents attended church services, in 1893, members of the club came up with a solution, known as “Never on a Sunday” that continues today.
Members of the community created the Tournament of Roses Association to take over the annual parade.
[3] Almost ten years since the first Rose Parade, the tournament became a larger festival that gained popularity in many other cities, and eventually cross-country.
After the first production of automobiles, the Tournament of Roses Association allowed motor vehicles to be used as floats, as long as they were in the back of parade where they would not disturb and scare the horses.
[5] Tournament of Roses Association carefully chooses participants who will represent their local community.
During the early parades, floats were carried by horses and carriages that transported local dignitaries and resident elites.
Although participants continue the tradition of decorating floats exclusively with flowers, the use of new technology such as computerized animation, and robots[3] has also been incorporated into design.
[4] One of the primary and most enforced rule of the float is that structure must be completely covered in flowers, petals and other vegetable materials such as “seeds, leaves and stems”[4] Some flowers used in floats include roses, orchids, chrysanthemums and different types of blossoms.
[3] There are three different types of entries in the Rose Parade; floats, marching bands and equestrian units.
Large commercial floats attract more attention due to the amount of time and money invested.
[4] Themes can be interpreted in many ways and designers can get creative and express meaningful, important messages within their floats.
The collaboration between the volunteers provides a community bonding that is rewarding to the people involved in the design, construction and decoration process of the floats.
Characters and other objects on the float are created as separate elements to add later, consisting of a framework of steel and chicken wire.
The float is then "cocooned" in the next process; it is sprayed with a polyvinyl material which acts as a base for inserting decoration.
Every square inch of the exposed surface of a float entered in the parade must be covered with flowers or other natural materials.
In the old days, some of the flowers used on the floats were home grown in the former Fanny Morrison Horticultural Center, now the Kidspace Children's Museum in the Arroyo Seco Natural Park.
Recent Sweepstakes Trophy winners for the "Most beautiful entry: encompassing float design, floral presentation and entertainment":