Puya berteroniana

The Puya berteroniana is a remarkable Chilean perennial that will delight botanical enthusiasts. This Chilean cousin of the pineapple offers one of the most spectacular flowerings in the plant world. While it takes time and only appears on plants at least 6 years old, its flower spike is stunning: massive, reaching heights of up to 4 m (13ft), it bears countless tulip-like flowers that appear to be from another world. Woven from turquoise blue satin with metallic reflections, punctuated with orange stamens, they are filled with nectar that birds adore. This flowering often marks the death of the rosette that carries it, but the plant ensures its survival through daughter rosettes and spontaneous seedlings that germinate under favorable conditions. Still rare, this exotic puya, which is not as tender as it seems, is starting to make its appearance in our gardens with mild climates. To showcase it, give it a large, well-drained rockery and a sunny or partially shaded exposure in our warm and dry regions.

The Puya berteroniana belongs to the bromeliad family. It is native to the Valparaiso and Santiago regions of Chile, dominated by a Mediterranean climate with dry summers and relatively mild and humid winters. It is found on the northern slopes of the Andean foothills, covered by scrub vegetation called matorral: in the Southern Hemisphere, north-facing slopes receive the most sunlight. This high-altitude botanical species (1200-2300 m (3937-7546ft)) can tolerate short freezes of around -7/-8°C in well-drained soil. It grows in poor, rocky, dry, basaltic (alkaline) soils. Its foliage persists throughout the year.

The plant develops slowly, forming a rosette of basal leaves that spreads horizontally and produces shoots late in life. The leaves, which can reach up to 1 m (3ft) in length, form a fountain-like clump, eventually occupying a space of 2 m (7ft) in all directions. They curve towards the ground, are very narrow, leathery, pointed, covered in a wax-like coating, and bordered by formidable spikes in the shape of hooks. Their colour, greener in winter, takes on silvery reflections in summer due to heat and drought. Flowering usually occurs in late spring in our latitudes, in May-June. From the centre of the mature rosette, a green almond-shaped flower spike emerges, covered in flower buds. The first flowers open on the main stem, which then branches into sterile secondary stems on which birds perch. The flowers, with three fleshy and glossy petals, iridescent turquoise blue in colour, form deep cups, and are numerous and tightly packed together. Each flower measures 3 to 4 cm (1 to 2in) in diameter and has three stamens covered in orange pollen. They are filled with a syrupy blue nectar that birds and large pollinating insects delight in. After pollination, the plant produces a large quantity of seeds, of which only a few will germinate. If the flower spike is removed before seed formation, the rosette may not perish. The Puya berteroniana usually persists through the development of daughter rosettes that emerge near the base.

This fabulous Puya berteroniana is a collector's plant that deserves a prime spot in our gardens with mild climates. It can be placed in a large exotic rockery, for example, alongside Yucca, modest palms, Phormium, or hardy tall cacti such as Echinopsis, Cereus strausii or aethiops for example. The light shade of certain trees does not prevent it from flowering in warm regions. It can be cultivated without difficulty on a terrace, where it will reign in a large pot filled with sand and compost, to be stored (handling it with caution as it is very "hooked") in a greenhouse or conservatory to protect it from severe frosts. It is undoubtedly one of the most extraordinary species of Puya: its cultivation in open ground is definitely worth trying in mild regions. According to our own experience, it seems to tolerate slightly alkaline (but light) soils well and withstands summer drought.