Fall is a lovely time of year, with the comfortable weather and vibrant displays of color, but its majesty is tainted knowing that winter will soon follow. With that first frost, the pretty (and expensive) annuals that lent so much color to the yard are gone in an instant.
This does not need to be the case, as many of the plants we call annuals are cold-intolerant perennials. Plants such as begonias, New Guinea impatiens, geraniums, coleus and even vegetables such as eggplant, peppers and most herbs can be brought inside, winter in warmth, and be returned to the garden next year. All that is needed is a sunny window, but a fluorescent light fixture hung within 10 inches over plants can be used instead if more space is needed.
The plants do not really do much over winter, and some watering and monitoring will be required. At best, they might grow a little, but most likely they will sit and look sickly. Remember, the goal is to have the plants survive until next spring, not to move your summer garden indoors.
In the next few weeks in October, pot up plants using a light potting mix and a pot with drainage holes. Prune plants back to a denser size to help the plant cope with the shock and encourage root growth. If possible, blast off any bugs with a hose prior to bringing inside.
Keep the plants separated from any houseplants, so that bugs are not transferred to them. Eventually, they can be moved to a new spot. As days grow shorter, decrease watering, as the plants will be growing very little. Plants might even start to lose their leaves, which is a normal way they cope with dramatic changes in light conditions. New leaves should start growing in a few weeks.
Most critically, monitor and treat when pests appear. Aphids and other insects thrive in sheltered conditions, so be prepared to deal with this possibility.
When late spring approaches, start to acclimate the plants back to outside conditions, and plant them after the danger of frost has passed.
If space is limited, cuttings from geraniums, coleus and New Guinea impatiens can be rooted in potting soil and a new crop of plants can be started. This method yields healthier plants, but requires more care over the winter. Overwintering plants can save money and fuel your need to garden in the winter, all with very little investment.
Jim Stendler is a University of Illinois Extension master gardener for Kane County. The “Learning to Grow” column runs weekly during warmer months of the year. Call the extension office at 630-584-6166 for more information. Feedback on this column can be sent to firstname.lastname@example.org.