Celosia flowers are in the Amaranthaceae family and are basically of two groups. The variety shown here is the plumosa group. It’s the more popular of the two, often grown in flower beds, containers, and indoors as house plants. Celosias are one of the most eye-catching annuals to grow in the garden. Technically speaking, however, they are tender annuals, as they are perennial in Zones 10 to 12.