The Flower Show at the D.C. Armory has attracted more than 50,000 people with a nose for spring and when it closes for good at 8 tonight additional thousands are expected to have sniffed their first hyacinth of the season.

Another flower show opens at 11 this morning at Capital Centre, call the Washington International World of Plants and Flowers, with a 60-foot high "recreation" of the Hanging Gardens of Babylon.

The Flower Show (as it is called without any further qualifications) at the armory includes about 45 exhibits and a number of trade stands. The Smithsonian Institution has the most striking display, a small garden of colored foliage plants worked into a design like a rug or wallpaper.

It is considered an interesting period piece dating from about 1870, and the bed is fenced with black iron railing with iron urns and benches inside.

An "international" section of the show is in the bassement, and Republic of China (Taiwan) shows a beautifulmass of orchids flown in for the show.

Specialized plant societies (camellias, rhododendrons, daylilies, etc.) operate booths presenting information about their treasures, with small exhibits of a few blooming plants.

Various nurseries have created small gardens with paving, little pools, grass, furniture and plants.

Bernald Nees, the show chairman, said it cost $200,000 to produce the Flower Show, with the exhibitors spending an additional $300,000 to prepare and install their exhibits. A number of forced tulips and hyacinths white-painted wooden gazebos.

Here and there one spots an attractive little exhibit of begonias by the University of Maryland or some tropical ferns from the U.S. Botanic Gardens.

The National Arboretum has a small display of Japanese plans, and sprigs of conifers and broadleaf evergreens have been offered in a competitive class by amateurs, along with some orchids (a stunning bucket of cymbidiums by Earl Godfrey of Capitol Hill Garden Club).

Lectures today at the armory will deal with orchids at 11 a.m. bonsai at noon; pesticide safety at 2 p.m.; dangerous (pisonous) plants at 3 p.m.; insect pests at 5 p.m.; bonsai at 6 p.m.; and gardening books at 7 p.m. The show is low-keyed, and gardeners will not find an elaborate use of large plants, architectural backgrounds and exciting model gardens, such as may be seen at the nation's major shows, but this is the first garden show of its kind in seven years, various amateurs said, and doubtless marks the beginning of a tradition of large and elaborate spring shows.