Alternanthera ‘Red Carpet’ Delivers Rich Color from Spring to Frost
Alternanthera ‘Red Carpet’ is a stunning ornamental cultivar prized for its deep burgundy foliage and elegant mounding form. Often called Joseph’s Coat or Joyweed, this variety features slender leaves in bold red and purple shades, creating dramatic contrast in both garden beds and containers. With a spreading habit and vibrant hues that deepen in full sun, ‘Red Carpet’ is a top performer from early spring through the first fall frost.
It is part of the Amaranthaceae family of plants. Alternanthera species are native to tropical and subtropical regions. They grow them as annuals in temperate climates. The ‘Red Carpet’ cultivar brings uniformity, strong color saturation, and exceptional heat tolerance, making it a favorite for mass plantings, borders, and cascading container displays.
How to Grow Alternanthera ‘Red Carpet’
Light
This cultivar performs best in full sun, which intensifies its foliage color and promotes dense growth. It can tolerate partial shade, but leaves may turn more greenish or dull in low light. Ideally, provide at least 6 hours of direct sunlight per day for the richest burgundy tones.
Soil
Alternanthera prefers moist but well-drained soil with good organic content. A garden bed enriched with compost or a container mix with perlite or bark for aeration works well. Avoid heavy, compacted soils, especially in rainy climates.
Watering
Keep the soil consistently moist, especially in hot weather, but never soggy. Allow the top inch (2.5 cm) of soil to dry out slightly between waterings. Overwatering may lead to root rot or fungal diseases like botrytis in humid conditions.
Fertilizing
Feed ‘Red Carpet’ every few weeks with a balanced, water-soluble fertilizer during the growing season. In containers, you can use a constant-feed program at 200 ppm nitrogen to maintain vigor and color. Alternatively, incorporate compost into the soil at planting time to improve fertility.
Alternanthera ‘Red Carpet’ in the Garden
This cultivar reaches about 45–60 cm (18–24 inches) in height and spreads 60–90 cm (24–36 inches), forming a dense mat of foliage that serves as a vibrant carpet across the soil. It’s a superb choice for edging paths, filling in sunny groundcover areas, or adding color contrast in container gardens. Its trailing habit also works beautifully in hanging baskets where the foliage can cascade over the edges.
The plant doesn’t usually require pinching, but light shaping may be helpful to direct growth or encourage fullness. Because it doesn’t stretch excessively, plant growth regulators are typically unnecessary.
Propagation and Planting Tips
Alternanthera ‘Red Carpet’ is easily propagated from stem cuttings. Take 4–6 inch (10–15 cm) cuttings from healthy plants, strip the lower leaves, and root them in moist soil or water. For greenhouse growers, maintaining a pH between 5.5–5.8 and spacing plants to allow sunlight to reach the base helps ensure even color development and air circulation.
When planting outdoors, wait until after the last frost date. This warm-season annual does not tolerate cold and should be protected from early or late-season chills. In USDA Zones 10–11, it may survive as a tender perennial, but it’s generally treated as an annual elsewhere.
Pests and Diseases
Whiteflies and aphids can occasionally be problematic, especially in greenhouse settings or hot, dry weather. Monitor plants regularly and apply insecticidal soap or neem oil as needed. Alternanthera is not prone to many diseases, but botrytis can occur in overly wet or crowded conditions. Prevent this by spacing plants adequately, watering in the morning to allow leaves to dry, and providing good air movement.
If treating botrytis, fungicides like Medallion or Banrot can be applied as a drench according to label instructions. However, cultural practices like proper spacing and watering go a long way in preventing issues altogether.
Seasonal Use and Design Ideas
Alternanthera ‘Red Carpet’ performs from early spring to frost and shines in both formal and informal settings. Its velvety foliage pairs beautifully with lime green, silver, or golden-leaved plants for contrast. Try combining it with Coleus, Sweet Potato Vine, Dusty Miller, or ornamental grasses. In containers, use it as a cascading element, or mass it in beds for a solid, eye-catching ground layer.
Its bold color and neat growth habit make it ideal for municipal plantings, park borders, and home landscapes alike. Whether spilling from a window box or lining a walkway, ‘Red Carpet’ lives up to its name—rolling out a plush, red welcome wherever it’s grown.
