What a relief, not to have to worry about the plants in our gardens, which are safely tucked away under an insulating blanket of snow. But don't let your green thumb get rusty. There are some gardening chores to tackle indoors in December.
Because days are so short now, most houseplants will benefit from being moved to locations near brighter windows. That includes flowering holiday plants such as poinsettias, kalanchoes and Christmas cactuses, as well as the foliage plants you enjoy year-round.
Don't place plants too close to a window pane, though. That can cause leaves to develop symptoms of chilling injury -- watery-looking spots or cupped, deformed new growth -- even though the leaves don't actually freeze. Drawing the drapes or lowering blinds or window shades as night falls will help protect the plants from the cold.
Watch for invaders
If you have a Christmas tree or garlands or wreaths made from pine or fir boughs, scout your plants for signs of spider mite infestation. Mite eggs can come in on these conifers, then hatch in the warmth of your home.
Spider mites don't fly, but it's easy to move them accidentally from one site to another. Look for fine, silky webbing and pinprick discoloration, primarily on the undersides of leaves. If you catch an infestation early, you can usually control it with repeated applications of insecticidal soap.
Move with care
If you're buying a new plant for yourself or to give as a gift, be especially careful transporting it from the florist's or garden center in the cold weather. Don't leave any live plant unattended in your car while you run errands. Get it into a warm building as soon as possible.
If you're buying a gift and you need to keep it for a day or two, open the top of the wrapping and put the plant in a bright place, out of direct sunlight. If you have to keep the plant longer, unwrap it completely so you can water it. Before you deliver it, rewrap it carefully and make sure none of the plant is exposed to the elements.
For fast flowers
Pick up some paperwhite narcissus bulbs to start indoors. They need no special cold treatment to make them bloom. Just plant them in potting soil or anchor them in decorative pebbles in a shallow container, then add water just to the base of the bulbs.
Some gardeners advocate setting them in a dark closet for a week while the roots grow, but I've had good luck putting them right into a cool, sunny window.
Their flowers last longer in a cool place, and the bright light helps prevent them from growing too tall and floppy. Paperwhites aren't winter-hardy in Minnesota, so once they're done blooming, throw them away.
Inspect your harvest
Check garden produce stored in your basement to make sure it's still firm and healthy. Onions and potatoes will soften and sprout if they've been kept too warm. Turn winter squash to look for soft areas and other signs of deterioration. Inspect stored cannas, callas, dahlias and other summer bulbs too. Discard any that are going bad, before the problem spreads to the rest of the bulbs.
Deb Brown is a horticulturist with the University of Minnesota Extension Service Yard and Garden Clinic. For help with garden, plant and insect questions, call the Extension service at 612-624-4771.