Spring was guest of honor yesterday as the Washington Flower and Garden Show opened in a bower of azaleas, daphnes, roses and the other oddments that persuade gardeners they are going to live, after all.

A smaller show than the well-known efforts of Philadelphia and Boston, the Washington show is handsomely designed by Oehme, Van Sweden & Associates. The exhibits are tasteful and flower-packed, with occasional jewels like Clematis armandii in full bloom, and the trade exhibits well designed and often fascinating, as in a display of irresistible moderately priced cacti raised from seed.

Dr. Henry M. Cathey, director of the National Arboretum, was responsible for the centerpiece garden, featuring a particularly fine deep rose Chinese magnolia. The walkways among the small gardens and floral displays are uncommonly and usefully wide, making traffic a pleasure instead of a hassle .

Early visitors yesterday marched about like dogs with two tails except for one man, Thomas J. Stafford, who is show producer and who has hardly seen a bed since Saturday. His eyes focused on a display of bush roses but all his mind saw was a celestial vision of a mattress, it was learned.

The show at the Convention Center continues through Sunday, opening at 11 a.m. and closing at 10 p.m. through Saturday and 8 p.m. Sunday.