Antigonon, also called coral vine, queen’s wreath, or cadena de amor, is a genus of climbing plants from the family Polygonaceae. This small genus includes the common species Antigonon guatimalense, cinerascens, and leptopus. Cultivation of these plants is widespread in the tropics and sub-tropic regions, particularly in the Americas, India, and the Philippines. They are used as food sources, herbal plants to treat certain medical ailments, and ornamental plants because of their abundant and colorful flowers. These plants are vulnerable to cold temperatures, but they flourish in sunny conditions and may exhibit invasive growth.
The species of this genus mostly share the same characteristics. Their tendrils grow rapidly and intertwine with any objects within their vicinity. They can grow to a length of 30 to 40 ft (9 to 12 m). These plants have dark green, hairy or pubescent, heart-shaped leaves that are 4 in (12 cm) wide, along with pink, red, or white flowers that grow in bunches. The petals surround a cone-shaped, nut-like fruit.
Unlike leptopus and guatimalense, Antigonon cinerascens display flowers with yellow instead of red hues. Both the cinerascens and leptopus have orange or red anthers, while guatimalense has black anthers, as well as broader leaves and denser pubescence. The flowers of guatimalense have ruffled edges, while those of cinerascens and leptopus are smooth.
Antigonon is used by some gardeners as an ornamental plant. Many butterflies and bees are attracted to its brightly colored flowers, which aid in their rapid propagation. Their bright and dense flowers are used in flower arrangements and decorations. Gardeners and landscapers use them as coverings for fences, trellises, and arbors because of their thick foliage to provide privacy and shade for other plants. They can thrive in urban environments because of their overall hardiness and ability to withstand pollution and poor soil.
In some countries in South America and Asia, Antigonon tubers and flowers are consumed. The aerial parts like the leaves, flowers, and stems are used to prepare concoctions to alleviate pain and cold symptoms. Extracts from various parts of the plant have shown anti-inflammatory, analgesic, and anti-diabetic properties in some studies.
The vining behavior of these plants is at its most aggressive in places where there is plenty of sunshine all year round. Antigonon tolerates moist or dry soil and sunny or shady areas. It withers and dies during winter season due to cold damage, but it quickly sprouts back once the conditions are warmer. The fast growing behavior and general hardiness of these plants have caused them to become a problematic weed in many areas of the world. Regular pruning can prevent them from spreading to take over other plants.