Planted in spring, coleus provides season-long interest, dying back with the first frost.
Unlike coleus in the garden, indoor coleus lasts for several seasons.
Coleus is toxic to pets.
The Spruce / Cori Sears
Newer cultivars, like the Wizard series, are more tolerant of sun than older types.
Most varieties are suited to shady spots and do well with morning sun and afternoon shade.
Soil
Coleus prefers consistently moist, rich, well-draining soil with a pH between 6.0 and 7.0.
The Spruce / Cori Sears
Before planting, amend the soil withcompostor another organic material.
For potted plants, use a good-quality potting mix.
Water
The soil in which coleus grows best should be consistently moist but not soggy.
The Spruce / Cori Sears
Long dry spells slow the plants growth, and leaves start to brown around the edges.
Containers need water more often, up to twice a day during hot weather.
Mulching helps retain moisture (avoid cedar mulch, which may render the soil too acidic for coleus).
The Spruce / Cori Sears
Temperature and Humidity
Coleus thrives in hot, humid conditions.
Light frost kills large-leaved types.
Wait until the temperature reaches 70F before moving potted plants outdoors in spring.
The Spruce / Kara Riley
Keep indoor plants away from air conditioner vents and drafts.
Fertilizer
Coleus is sensitive to fertilizer, which, when overused, leeches color from the leaves.
When grown in rich soil, feeding isn’t necessary.
Amend the bed beforehand or add a balanced slow-release fertilizer at planting time.
Feed container-grown plants once a month with a water-soluble fertilizer.
Want more gardening tips?
Is This the Right Plant for You?
New cultivars are developed each year, and garden centers tend to focus on a select popular few.
Shop several different places to find more unique varieties.
Using pruning shears, pinch just under the flower buds to promote leafy growth instead of flowers and seeds.
Plants that are not pruned tend to get leggy and lose their shape.
Propagating Coleus
Coleus plants are best propagated by takingstem cuttings.
In these situations take several cuttings to improve your chances.
But seed companies sell coleus varieties that are worth growing from seed, which is easy.
For planting outdoors,start seeds indoorsabout eight to 10 weeks before your last frost date.
A few insects on a plant can often be controlled with a strong spray from a garden hose.
If the infestation is severe, you might have to resort to an insecticide such as insecticidal soap.
Mulch discourages slugs.Groundhogsand youngrabbitswill nibble your coleus leaving them with an unsightly ragged appearance.
Coleus is not usually bothered by disease.
In cool, damp weather, fungal diseases such aspowdery mildewmay appear.
Good drainage prevents root and stem rots.
Common Problems With Coleus
Coleus is a reliable, showy foliage plant with few problems.
Fungal infections usually start during periods of cool, humid weather.
Overwatered plants develop yellow, mushy leaves.
Underwatering causes foliage to fade, yellow, and turn brown and crispy.
Too much fertilizer interferes with chlorophyll production.
Choose the correct pot size starting out.
Rootbound coleus also develops yellow leaves.
Fuzzy gray and purple spores appear on the undersides of leaves affecting lower leaves first.
Avoid overcrowding plants for better air circulation and water in the morning.
confirm the variety you choose is suited to sun exposure for the intended garden spot.
Water new transplants in well and keep soil moist but avoid overwatering.
When purchasing coleus, big is not always better.
Coleus is a tender perennial hardy only in U.S southernmost zones 10 and 11.
In zones 7 and higher this annual may reseed but it you’ll have to allow it to flower.
Height and spread depend on variety.
Cultivars grow from 6 to 36 inches tall and wide.
Most coleus varieties can grow well in both sun and shade.
Most types are suited to shady spots and do well with morning sun and afternoon shade.
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