Q. Can I grow the annual Coleus indoors?
Although coleuses are perennials in zones 10 and 11, most growers treat them as annuals, temporary foliage plants, to be enjoyed and then discarded when past their best. This is because they are sometimes difficult to overwinter in your home and also are easy to grow from cuttings.
One species, C. blumei is commonly grown as a house plant. Some of its forms have heart-shaped leaves, and others have slender, sometimes contorted, pendulous leaves. Young seedlings are only an inch or two high. Named hybrids of this species are also frequently available and if you happen to find these hybrids you can grow them easily by providing them with bright light at all times, and several hours a day of direct sunlight. Insufficient light will result in spindly, elongated growth. Temperatureshould be kept above 65 degrees; the air should be humidified by standing plants on trays of damp pebbles or moist peat moss.
You can try to use your annuals from your garden outdoors, but they may not grow well due to lower light conditions. Make sure no pests are on your plants from outdoors though. Dig up healthy plants in the fall just before cold weather hits. Make sure you get as much of the root system as possible. Pot your plants in suitable containers with well-draining soil and water them thoroughly. It may also help to trim back the top half of growth to reduce shock, though this is not required.
Allow your plants to acclimate for about a week or so prior to moving them inside (if done in August). Then place the newly potted plants in a sunny location, such as a south- or southeast-facing window, and water only as needed. If desired, you can include half-strength fertilizer once a month with your regular watering regimen. You may also want to keep new growth pinched to maintain a bushier appearance. In spring you can replant the coleus back in the garden.
Courtesy of NYBG Plant Information Service
Hope this is helpful.