Coleus are prized for their colorful foliage which may combine shades of green, yellow, pink, red and maroon. New introductions of this popular annual have been selected for increased sun and heat tolerance.
Coleus vary from smaller types that will reach only 1 foot tall to tall bushy types of 3 feet. Sprawling types suitable for hanging baskets and wall plantings may spread up to 3 feet or more.
Most coleus grow fairly rapidly to their full summer size. They are all tender annuals throughout South Carolina and will be killed by the first frost.
The brilliant and widely varied colors of coleus foliage make it a natural for use in summer bedding and as a color accent. Victorian “carpet bedding” relied heavily on coleus for its bright and intricate patterns. Coleus also grows beautifully in containers, which can be used to highlight patios, porches and garden terraces.
Coleus are highly resistant to serious disease or insect problems when grown outdoors in properly prepared beds or containers. Some pests to watch for include mealy bug, aphids and whitefies. Some disease problems to watch for include stem rot and root rot.
Most coleus will grow best in part shade or dappled light. However, several sun tolerant cultivars are available that will thrive in full, hot sun. They are listed in the cultivar listings below. Varieties that are not sun-tolerant will bleach and discolor in full sun.
Coleus must have good soil drainage. Poorly drained soils and excessive watering will damage coleus. Plants suffering from “wet feet” will be stunted, leaves will turn a muddy brown, and leaf margins will be scorched.
Plants should not be allowed to dry out, however. Water in thoroughly at planting. During the first seven to 10 days, keep root balls moist but not overly wet. Thereafter, water only when top inch of soil is dry (check with your finger every three to five days). Use of soaker hoses is highly recommended.
Coleus grown in containers are more susceptible to drought and should be planted in a very well-drained soil mix that is watered more frequently.
Pinch growing shoots of young plants frequently to encourage and maintain dense foliage. For a mid-summer growth boost, fertilize in June, July and August with a liquid fertilizer at half the usual dilution.
Flower spikes will appear in late summer. Many people dislike their appearance, and if allowed to go to seed the plant will decline. Shear back flowers to extend performance. Vegetative coleus are sterile forms that must be grown from cuttings. They generally flower little in the summer and require less maintenance than seed-grown coleus.
Since coleus are annuals and will be killed by the first fall frost, you may want to take cuttings of especially prized cultivars. They root easily from stem cuttings at any season. Common coleuses can also be grown from seeds.
- ‘Alabama Sunset’ is an old favorite but still exceptional for its tolerance of sun. The brick-red leaves have a thin yellow edge. ‘Alabama Sunset’ is a vegetative, or sterile, coleus that blooms little and requires less maintenance.
- ‘Burgundy Sun’ is another coleus from Texas. It has large, oval to heart-shaped leaves that are deep, rich burgundy in color. It grows 2 to 2½ feet tall and is slow to flower.
- ‘Pat Martin’ is a large plant with burgundy leaves with yellow-green edges. It is a vegetative coleus.
- ‘Pineapple’ is bright lime-gold with burgundy stems. This easy-to-grow cultivar seldom blooms.
- ‘Plum Parfait’ has purplish plum-colored ruffled leaves that develop pink margins. Developed in Texas, it is very heat-tolerant.
- ‘Saturn’bold and distinctive with deep burgundy leaves with a lime-gold center and a thin, scalloped lime edge. Grows to 2 feet tall.
- ‘Solar Flare’ has wide, heavy leaves of parsley green, with a red center and deep yellow fringe.
- ‘Solar Eclipse’ has serrated cherry red leaves with black markings.
- ‘Solar Furnace’ is deep red.
- ‘Solar Shadow’ is green with deep red serrated edges and tips.
- ‘Solar Spectrum’ is multicolored green, red and bronze with serrated edges.
- ‘Solar Storm’ has dark red, green and ivory deeply cut leaves.
Coleus That Grow Best in Part Shade
- ‘Black Magic’ has mahogany purple leaves outlined in avocado scallops.
- ‘Brilliancy’ is an old upright variety with bright red leaves and green scalloped edges
- ‘Dark Star’ is the darkest of all the black coleus.
- ‘Duckfoot’ forms compact dwarf globes with tiny lobed, deep purple leaves. This non-blooming miniature is excellent for bed edging.
- ‘Fishnet Stockings’ has lime-green leaves, heavily veined in dark purple.
- ‘Freckles’ is polka dotted, green with red freckles.
- ‘India Frills’ forms compact mounds of tiny, finely cut leaves with elaborate ochre, pink and purple designs. This is a very low carpet coleus.
- ‘Japanese Giant’ has enormous leaves of pink and violet on a base of burgundy.
- ‘Mardi Gras’ has red, green and yellow leaves and a compact growth habit.
- ‘Purple Emperor’ has deeply ruffled, solid black-purple foliage.
- ‘Red Ruffles’ has red, wavy leaves and green margins.
- ‘Sunset’ is a compact variety with terrific russet-red foliage all season.
- ‘The Line’ is tall with elongated gold leaves with a line of deep purple along the mid-vein.
- ‘Thumbelina’ has tiny, rounded leaves of green and burgundy on a compact plant.