Store clearly labelled liquid fertilizers, pesticides, and herbicides where they will not freeze. Place dry materials like granular fertilizers, pesticides, and herbicides in sealed plastic bags or containers and store where they will not be exposed to moisture. Make sure all materials are out of reach of children and pets. If you have some pesticides or herbicides you don't wish to store over the winter, check with your municipality for the correct way to dispose of hazardous waste in your community.
Heavy snow and ice can cause the branches of columnar evergreens with multiple leaders such as junipers and arborvitae to splay out and break, destroying the plant's natural form. To help them shed snow without breakage, crisscross the entire crown of smaller trees with nylon cord to hold the branches together. The leaders of larger trees can be tied together in the interior about two-thirds of the distance up from the crotch where they divide to the top of the tree. Use a soft material like old pantyhose or strips of cloth so you don't injure the bark. Remove all ties and wrappings promptly in the spring.
Fungus gnats, those tiny dark flies that fly out when the leaves of houseplants are disturbed, generally don't do much damage to plants, but they are a nuisance as they flit about. To discourage egg laying by female flies, spread a thin layer of sand over the top of the potting mix in the container. To make conditions less suitable for the larvae in the soil, allow the top couple of inches of potting mix to dry out between waterings.
Perusing gardening books for inspiration and sketching out new garden and landscape plans is one of the most enjoyable ways to spend a cold winter afternoon. Get ready for this activity by taking measurements and photos of outdoor areas before the snow flies so you have pictures and figures handy to help you as you plan changes and additions to your landscape.
Once the ground has frozen, but before the snow flies, mulch newly-planted or shallow-rooted perennials with a loose organic mulch that won't mat down, such as straw, pine needles, bark mulch, or chopped oak leaves. Spread the mulch 2-3 inches deep around plants. The idea is to insulate the soil to keep it from going through alternate freeze-thaw cycles during the winter that cause plants to be heaved out of the ground, exposing roots to injury from cold and drying.