"Along comes this crush of cold, and the dwarf iris and crocus are - forget it," Mr. Letts said.

Signe Nielsen, a city landscape architect, has put together a collection of handmade birdhouses in a whimsical environment of huge cracked egg shells full of dwarf iris, muscari, cyclamen, giant allium and many other seasonal flowers.

Visitors can also see grape hyacinth, brilliant blue scilla, anemones, tulips, dwarf iris and violet crocus.

A few favorites, in their approximate order of spring appearance, are the winter aconite, snowdrop, crocus, dwarf iris, squill, miniature daffodil, botanical tulip, grape hyacinth and daffodil.

Species crocus and dwarf iris come up in February, and the water lily tulip (Tulipa Kaufmanniana), with its white petals and egg-yolk-yellow centers, blooms from March to April.

The bluish-violet and yellow flowers of the last dwarf iris were fading but still colorful, and fernleaf peonies were in full bloom.

Crocus and muscari need 8 to 10 weeks cold treatment; dwarf iris and snowdrops, 10 to 12 weeks.

Other wildflowers are spring beauty, hepatica, crested dwarf iris, barren strawberry, fairy bells, wild oaks, shortia, bloodroot, red and white trilliums and a double white trillium with a ruff of petals, windflower, shooting star, Canada anemone and wild ginger.

Open spaces between the rocks are filled with flowers needing room for expansion like may apple, crested dwarf iris (both blue and white forms) and wild ginger.

Shortly thereafter, the soft yellow or violet triangular blooms of dwarf iris appear.