The hybrid plant Alternanthera ‘Choco Chili’ is widely sought after for its striking, deep-colored foliage that brings dramatic contrast to garden beds and containers. This mounding, shrubby plant has nearly black-purple leaves on the top surface, contrasted by a vibrant, ruby-rose underside and red stems. Growing to a height of about 8 to 14 inches and spreading up to 18 inches, this cultivar offers a naturally compact habit, making it an excellent choice for ground coverage or as a “thriller” in pot arrangements.
Ideal Site and Soil Preparation
Alternanthera ‘Choco Chili’ thrives in full sun exposure, which is necessary to achieve the darkest pigmentation in the foliage. While the plant can tolerate partial shade, insufficient light will result in a leggy growth habit and duller leaf color. Native to tropical regions, it prefers consistently warm temperatures and is generally grown as an annual outside of USDA Hardiness Zones 9 to 11.
The soil must be well-drained, as the plant is susceptible to root problems in soggy conditions. A rich, loamy soil composition amended with organic matter provides the best foundation. When planting in a container, use a high-quality potting mix designed for good drainage. The ideal soil pH range is slightly acidic to neutral (5.5 to 6.2), which helps the plant efficiently absorb necessary nutrients.
Essential Daily and Weekly Care
Consistent moisture levels are necessary for healthy growth, but overwatering must be avoided to prevent fungal issues like root rot. Keep the soil consistently moist but never waterlogged, which is challenging in containers that dry out quickly. Deep watering once or twice a week is a good starting point, but frequency should be adjusted based on weather conditions. If the plant shows signs of wilting, it is likely too dry, but it will recover quickly once watered.
A regular feeding schedule will support vigorous growth and intense foliage color. During the active growing season, apply a balanced liquid fertilizer monthly, or use a constant feed program at a rate of 100 to 200 parts per million nitrogen. For optimal color, ensure the fertilizer contains micronutrients, especially iron, which is absorbed more easily in slightly acidic soil. In cooler climates, container-grown plants can be brought indoors before the first frost to be overwintered. During winter dormancy, reduce watering significantly and keep the plant in a well-ventilated location until spring.
Pruning and Troubleshooting
Pruning is an effective technique used to maintain the plant’s dense, bushy, and mounding habit. While Alternanthera ‘Choco Chili’ is naturally compact, periodically pinching back the growing tips will encourage lateral branching, preventing the plant from becoming long and leggy. This light, shaping prune can be done throughout the growing season as needed.
Aphids and spider mites are the most frequently encountered pests. For a non-chemical solution, a strong jet of water can dislodge small infestations, or insecticidal soap can be used to manage larger populations. The most common disease is Botrytis, a gray rot that appears in overly wet or humid conditions, especially during cooler days. Ensuring good airflow and allowing the soil surface to dry between waterings is the best preventative measure against this and other fungal problems.