Early spring can be a tough time for northern gardeners. We've already thumbed through our seed catalogs countless times. Houseplants just aren't doing it for us anymore. And even though the days are longer and warmer, it might be awhile until we can stick a shovel into the soil. But if you take a closer look, you'll see some encouraging signs of spring: PUSSY WILLOWS WAKE

A number of shrub willow species (Salix spp.) bear fuzzy silver-gray catkins in late winter or early spring. These showy catkins appear on male plants and often stay in the cute "kitty" phase for several weeks before a burst of yellow pollen-bearing stamens cover the catkins.

Cut pussy willow branches are great additions to spring bouquets. If you'd like to grow your own, good choices include large-catkinned European goat willow (S. caprea, zone 4), often called "French pussywillow," and the smaller-catkinned native pussywillow (S. discolor, zone 3). For giant-sized catkins, try Japanese pussywillow (S. chaenomeloides, zone 4) or rosegold pussywillow (S. gracilistyla, zone 4 or 5).

ALDERS PUT ON A SHOW

Are your alders (Alnus spp.) looking a bit shaggy? These moisture-loving shrubs and trees are early but subtle bloomers. Short, cylindrical male catkins have been dangling, tightly closed, on branches all winter. But now the reddish-brown catkins are loosening and expanding into cascading clusters of flowers with bits of yellow pollen showing.

Shrubby natives such as speckled alder (A. incana ssp. rugosa) are great for naturalizing near water features while tree forms such as European alder (A. glutinosa) make attractive midsized shade trees in moist soils.

SILVER MAPLES FLOWER

Silver maple (Acer saccharinum) is like the Rodney Dangerfield of the gardening world -- it gets no respect. While not the best tree for many residential lots, silver maple does have its good qualities. For one, when its clusters of tiny round flower buds start swelling in late February or early March, it's a welcome sign of winter's waning. The reddish, petalless flowers open in late March. They're not flashy, but hey, at least it's a start on the blooming season.

SNOWDROPS BLOOM

It's nice to appreciate tiny, subtle blossoms, but there's a point when you just want to see some real flowers. Though petite, the glistening green and white flowers of snowdrops (Galanthus nivalis) are a delightful sight in early spring

While they're not as showy as later-blooming bulbs such as Darwin tulips, snowdrops' hardiness and perseverance tell us we've all made it through another winter.

Nancy Rose, a horticulturist formerly with the University of Minnesota Extension, now works for Harvard University's Arnold Arboretum. This will be her last regular column for Home+Garden.