Red Outdoor Coleus - Care Sheet
Overview
Red Outdoor Coleus is a vibrant and popular tropical plant known scientifically as Coleus scutellarioides. Renowned for its striking red foliage, this plant is a member of the mint family (Lamiaceae) and is widely grown as an annual in temperate climates, though it is a perennial in tropical zones. It features colorful, serrated leaves that range from deep red to burgundy, often with variegated patterns. Coleus is valued for its ease of care, fast growth, and ability to brighten garden beds, borders, and containers with continuous color throughout the growing season.
Quick Facts
| Scientific name | Coleus scutellarioides |
|---|---|
| Common name | Red Outdoor Coleus |
| Difficulty | Beginner to Intermediate |
| Pet-safe? | Unknown; caution advised as some Coleus species may cause mild toxicity |
| Light | Partial shade to partial sun; tolerates full sun with adequate moisture |
| Water | Keep soil consistently moist but not soggy |
| Humidity | Moderate to high humidity preferred |
| Temperature | 18–29°C / 65–85°F; frost-sensitive |
| Soil | Well-draining, fertile, rich in organic matter |
| Fertilizer | Balanced liquid fertilizer every 2-4 weeks during growing season |
| Repotting | Annually or when root-bound |
| Propagation | Stem cuttings (most reliable), seeds (variable) |
Light
Red Outdoor Coleus thrives best in partial shade to partial sun. While it can tolerate full sun, especially morning sun, intense direct sunlight may scorch its leaves or cause fading of the vivid red coloration unless kept well watered. Ideally, provide bright, indirect light or filtered sunlight to maintain vibrant foliage. In hotter climates, afternoon shade is beneficial to prevent leaf stress.
Water
Keep the soil consistently moist but well-drained. Water thoroughly when the top 2-3 cm (1 inch) of soil feels dry. Avoid letting the soil dry out completely, which can lead to leaf wilting and loss of vibrancy. However, overwatering and soggy soil should be avoided to prevent root rot. Good drainage is essential.
Humidity
Coleus plants prefer moderate to high humidity levels, reflecting their tropical origins. If grown indoors or in dry climates, increase humidity by misting the leaves regularly or placing the pot on a humidity tray. Outdoor plants usually receive adequate humidity unless conditions are very dry.
Temperature
Ideal temperatures range from 18 to 29°C (65 to 85°F). Coleus is frost-sensitive and should be protected from temperatures below 10°C (50°F). In colder zones, it is best grown as an annual or brought indoors before the first frost. Sudden cold or heat stress can cause leaf damage and stunted growth.
Soil & Potting
Use a well-draining, fertile soil rich in organic matter. A high-quality potting mix with peat moss, compost, and perlite or sand works well. Good drainage is crucial to avoid waterlogging. For container planting, ensure pots have drainage holes. When planting outdoors, amend garden soil with compost to improve fertility and texture.
Feeding
Feed Red Coleus with a balanced liquid fertilizer (such as 10-10-10 or 20-20-20) every 2 to 4 weeks during the active growing season (spring through early fall). Avoid excessive nitrogen, which encourages leaf growth but can reduce leaf color intensity. Slow-release fertilizers can also be used at planting time for convenience.
Repotting
Repot annually or when the plant becomes root-bound, typically in spring. Choose a pot 2-5 cm (1-2 inches) larger in diameter than the current one. Refresh the potting soil to provide nutrients and improve drainage. Repotting encourages healthy growth and prevents the plant from becoming pot-bound.
Propagation
The easiest and most reliable method is stem cuttings. Take 7-10 cm (3-4 inch) cuttings from healthy, non-flowering stems, remove lower leaves, and root them in water or moist potting mix. Roots typically form within 1-2 weeks. Seeds can be used but are less common because cultivars may not grow true to type from seed.
Common Problems
Pests: Aphids, whiteflies, and spider mites
These pests can cause leaf distortion and discoloration. Use insecticidal soap or neem oil sprays and maintain good air circulation to control infestations.
Leaf scorch or fading
Often caused by too much direct sun or insufficient water. Move the plant to a shadier spot and increase watering frequency to restore foliage health.
Root rot
Results from overwatering or poorly drained soil. Allow soil to dry slightly between waterings and ensure pots have drainage holes. Repot with fresh, well-draining soil if needed.
Leggy growth
Occurs from insufficient light. Move the plant to a brighter location and pinch back stems to encourage bushier growth.
Flowering reduces leaf color
Coleus flowers can divert energy from foliage. Pinch off flower spikes to maintain leaf vibrancy and compact shape.
Toxicity & Pet Safety
The pet safety of Coleus is generally considered unknown or potentially mildly toxic. Some species in the genus can cause mild gastrointestinal upset in cats and dogs if ingested. It is safest to keep Red Outdoor Coleus out of reach of pets or supervise them around the plant.
Seasonal Care
In temperate zones, treat Red Outdoor Coleus as an annual, planting after the last frost and enjoying it through summer and early fall. Bring container plants indoors before frost or take cuttings to overwinter. In tropical or frost-free areas, it can be grown as a perennial with regular pruning to maintain shape and vigor. Mulch outdoor beds to retain moisture and protect roots.
Quick Tips
- Provide bright, indirect light or filtered sun for best foliage color.
- Keep soil evenly moist but well-drained to prevent root rot.
- Pinch back flower spikes to promote bushier growth and brighter leaves.
- Use balanced fertilizer every few weeks during growing season.
- Propagate easily by stem cuttings for new plants or to overwinter.
- Protect from frost and temperatures below 10°C (50°F).
- Watch for common pests like aphids and spider mites and treat promptly.