Celosia can bloom from June until frost. During that time, deadheading your celosia will encourage new blooms. Remove the flowers as they start to turn brown and loose color. If you wait too long after this point, seed development starts and the plant puts its energy into that rather than new blooms. Deadheading is not necessary in fall, as the plant is not likely to bloom again.
Celosia are tender perennials (in Zones 10-12) grown as annuals. Their inflorescences are brightly colored and showy--red, purple, pink, orange and yellow. The name celosia is derived from the Greek kelos, "burnt," referring to the flowers' fiery colors and often flamelike shape.
Although 50-60 varieties exist, commonly planted varieties belong to two species, Celosia argentea and Celosia spicata.Two forms of C. argentea are popular: the Cristata varieties (cockscomb) bear rounded,crested flower heads resembling enormous rooster combs or even cauliflower. Plumosa varieties feature erect, featherlike plumes. C. spicata, spiked cockscomb, is also known as wheat celosia for its narrow, spiky flower heads, reminiscent of heads of wheat. These plants produce numerous flowers, with an almost shrubby look.
Celosias make good cut or dried flowers. To dry, remove all the leaves from the stems and wrap a rubber band around 6-8 stems and hang them upside down from a coat hanger in a dark, cool, dry, airy space for several weeks or until fully dried. They will last in dried arrangements for at least six months without losing any of their vibrancy.
Southern Florida is in USDA Zones 10a and 10b so they should do fine there. Elsewhere in Florida they would probably need to be grown as an annual.