Overwintering Coleus Plants
Q: How can I overwinter coleus plants so I don’t have to buy new ones each spring?
A: The easiest method is to pot up stem cuttings. Most growers and home gardeners use this method in late fall to overwinter coleus plants or in early spring to increase their stock of hard-to-find cultivars.
To overwinter coleus, cut 3- to 4-inch tip cuttings from healthy plants. Remove the bottom set of leaves, dip the cut end in rooting hormone and place the cutting into a pot filled with a soilless mix. A 6-inch pot can accommodate 12 cuttings. Water well, cover with a clear plastic bag and move the pot to a shaded, warm location. In seven to 10 days when the cuttings have rooted, repot each into its own pot. Place the pots in a sunny window, water regularly and pinch back the growing tips throughout winter to promote a fuller shape. In spring, gradually introduce the plants to outdoor conditions. Coleus is very frost-sensitive, so bring the plants inside if cold nights threaten. By mid-May, the plants should be ready for your garden or containers.
Cuttings may also be taken from a large, healthy plant in late spring. Follow the above instructions with one change. After repotting each cutting into its own container, wait two weeks and then introduce cuttings to the outdoors. After May 15, the cuttings may be planted directly into a semi-shaded area of your garden.