You’ve grown used to the beautiful colors in your garden. You worked hard to choose colors that harmonize. You invested time and money to create the garden of your dreams. All good reasons to consider winterizing some of your annuals. Not all are genetically prepared to winter well and make a colorful comeback. But with some planning, positioning and care, some annuals will survive the winter indoors and be ready for re-planting come spring.
If you’d like to try winterizing some of your favorite annuals, here are the steps to take:
First, you’ll want to reduce the amount of energy the plant takes to survive the dormant months, so cut back its foliage. This is for plants that you are removing from the ground, as well as plants already in pots. You can be aggressive and cut it back by about one-third.
Second, if the annual is not potted already, you’ll need to lift the plant’s root ball from the garden and place it in a pot. Shake most of the garden soil from the roots and plant in a good quality potting soil.
Third, remove insect pests before they come into your home. Check leaves for spider mites and aphids. If you spot any signs, spray with insecticidal soap. If you don’t, spray with a strong spray from the garden hose just to be certain, aiming at the underside of leaves as well.
Fourth, location, location, location! Pick a window sill or glass door with a southern exposure. The more light, the better. Be certain that there are no drafts entering around the window. Since our homes tend towards dryness when the heat is on, you may need to add a humidifier near your plants.
Finally, care for your winterizing annuals as you would a house plant – minus any fertilizer. You’re looking for the plants to survive until spring and they will need to conserve any growth spurts until then. Water regularly but do not saturate soil.
The Cutting Method
Another way to bring back a favorite annual in the spring is by taking a cutting from it while it is thriving in the outdoors. The cutting should be 3” to 5” and is best taken from a non-flowering stem, so that the plant will direct its energy to producing roots. Place it in a jar of water, making sure that any leaves or buds are not submerged. Place in a sunny spot, a south or east facing window, and change water about once a week.
Which Plants do Best
The list of annuals that can be successfully winterized indoors is pretty long. The easiest are Coleus and Geraniums. Others include Alyssum, New Guinea Impatiens, Nasturtium, Pansy, Petunia, Verbena, Wax Begonia, Lantana, Viola, Dianthus and Nemesia.
What to Expect
Don’t expect the visions of loveliness your garden annuals provided outdoors. Indoors they will be leggy, drop leaves, and may even appear to be dying. But they are surviving, semi-dormant, as long as you are providing light and water. When temperatures warm up, set the potted annuals outdoors in the warm daylight to re-acclimate them to being outdoors. When there is no longer a danger of frost, re-plant in the garden or leave the pots outdoors. Keep in mind the cost of annuals is lower than perennials due to their short life span and bursts of color. You’ll have to weigh the amount of time and space available in your home versus annual shopping in the spring. While overwintering annuals is definitely possible, you’ll have to decide if it is preferable.