If you received a poinsettia or cyclamen as a holiday gift, keep it blooming by providing proper care. Poinsettias need good drainage, so if the pot is still wrapped in foil, make sure there is a hole in the bottom so water drains out. Of course if it's on furniture, place a saucer underneath to protect the finish. Keep poinsettias away from drafts, such as near doors or windows or hot woodstoves. Keep soil moist, but don't overwater. Keep in bright light.
The latter applies, also, to cyclamen which can last for weeks if kept cool (65 to 68 degrees F in day, less at night). Too high temperatures, too little water or overwatering, or too low light may cause leaves to yellow and drop.
When you're finished with holiday evergreen boughs, use them to mulch tender perennials and shrubs. They make a lightweight but insulating layer that helps protect plants from alternating temperatures like our typical January thaw followed by a deep freeze. Also they help trap snow over these plants, for a similar insulating effect.
While snow makes a good protective cover for plants, if you use salt to melt ice on driveways or walks, be careful not to pile snow from these areas on your plants or where melting snow will drain onto them. Otherwise, once snow melts in spring, flush it thoroughly with water to help dilute or wash away any salt residue.
Potatoes, onions, carrots, turnips, and other root crops that you have stored in your basement or root cellar should be checked regularly for signs of decay. Any vegetables that show any rotting should be removed and eaten (if possible) immediately so they don't spread the disease to other vegetables. If you've stored fruits such as apples, or summer bulbs such as dahlias, check them periodically as well.
With seed catalogs arriving in the mail, these short and cold winter days are a good time to browse through them or their websites. By starting your own seeds you can have cultivars (cultivated varieties) you won't find locally, you can save money, and it is just a fun process to watch those little seeds grow into seedlings.
Although you'll lean toward your favorites, why not try something you've never grown before, either a cultivar or crop. This year I plan to grow an heirloom-broom corn-which is actually a type of sorghum grain that is both attractive and quite tall. Last year, among other crops, I tried a new fusarium disease-resistant basil and yes, it did make great pesto. Consider flowers that grew best in our All-America Selections display garden at the Burlington Waterfront Park (perrysperennials.info/aaswp.html).
If you haven't grown your own fruits, consider this too, with links to sources and resources online (homefruitgrowing.info). While it is easy to visit local growers to pick and buy quantities of fruits in summer and fall, such as for freezing or canning or making jams, it's fun to grow some of your own. You often can grow fruits you won't find for sale, you'll have some for ready picking for immediate fresh eating, and you'll know what chemicals, if any, have been used on them. When choosing fruits, pay attention to the space they'll need, hardiness, and whether more than one selection is needed for cross-pollination.