Get a head start on weeding. Remove as many weeds as possible, giving priority to those already in flower. The more you hand-weed now, before seeds develop, the less you'll be tempted to use weed-killers later. Choose from a variety of tools to help you dig out all the roots - trowel, cultivator, soil knife, to name a few. I can testify that you can have a major impact on controlling weeds if you do it early. Five or six years ago, I tackled an aggressive population of chickweed ready to take over a shade garden. All these years later, the chickweed still hasn't returned.
Trim grasslike perennials. Low-growing, grasslike perennials such as Acorus and Liriope are normally evergreen to semievergreen throughout the winter. You can usually wait to cut the dieback from the previous growing season after the plants produce new foliage. However, being buried under snow and ice has left most of last year's leaves looking pretty ratty. Give these perennials a good trim with a sharpened pair of pruners or shears. Be careful to avoid nipping the tips of the new leaves just emerging from the soil. Once you've cleared away the winter damage, it won't be long before the plants fill out with new growth.
Mulch trees properly. A pet peeve of mine, shared by at least one reader of this column, is mulch "volcanoes" - cones of mulch material piled up around tree trunks. I'm on a crusade to free the trees from this unhealthy practice. Here's what you can do to help. Use the 3-3-3 rule promoted by the Pennsylvania Horticultural Society. Make the mulch layer three feet in diameter, three inches deep, and three inches away from the trunk (to prevent moisture from rotting the bark). Form the mulch into a saucer shape so that the saucer's lip holds water until it's absorbed into the soil.