Alcantarea rubra is one of the most popular giant bromeliads used in Australian landscape design. It is celebrated for its dramatic colour palette; while the upper surface of the leaves is a vibrant green, the undersides are flushed with a rich, dark burgundy or “rubra” red. When the plant is positioned where it can be seen from below, or when the leaves catch the sunlight, the red hues create a stunning visual glow.
This plant is a slow-grower but eventually reaches an impressive size, often spanning up to 1.5 metres in width. It forms a classic, large vase shape that collects water in its central tank. After several years of growth, it produces a spectacular, towering flower spike that can reach 2 metres in height, covered in small yellow flowers and red bracts. Like many bromeliads, the mother plant will slowly decline after flowering but will produce “pups” at the base to ensure the cycle continues.
Care Tips
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Position: Thrives in a position with full sun to dappled shade. Exposure to sunlight is essential to bring out the deep red pigment on the undersides of the leaves.
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Climate: Ideally suited to warm temperate, subtropical, and tropical Australian climates. It is quite hardy but must be protected from frost, which can cause unsightly spotting or damage to the foliage.
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Soil: Requires a very well-drained medium. It performs best in a chunky orchid-style mix or a potting soil enriched with bark and perlite. If planting in the ground, ensure the site is not prone to waterlogging.
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Watering: Maintain water in the central “urn” or tank of the plant. It is best to use rainwater or flush the tank regularly to prevent the water from becoming stagnant. The soil should be kept lightly moist but not saturated.
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Fertilising: Avoid high-nitrogen fertilisers as these can cause the plant to lose its red colouration and turn entirely green. Use a weak, diluted liquid seaweed or a slow-release fertiliser low in nitrogen.
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Pruning: Low maintenance. Simply trim away any old, spent leaves at the very base of the plant to keep it looking neat and tidy.
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Maintenance: Being a large plant, it can become very heavy when the tank is full of water. Ensure your pot or planting site is stable enough to support its weight.
