Yucca rostrata Sapphire Skies

Yucca rostrata 'Sapphire Skies' is a fashionable plant whose design is impossible to ignore: atop a very short trunk, a ball of fine, stiff leaves in a steel-blue colour unfolds, playing with the light. On mature plants, a monumental inflorescence forms, resembling a giant beak adorned with bell-shaped white flowers. It is one of those exotic yet hardy plants that originate in the cold winters and arid summers of North American deserts: this yucca brings an exotic touch and the breath of open spaces to our landscapes. Reserve a prime location for it in a dry garden or at the centre of a large rockery as it will be the centre of attention!

Yucca rostrata 'Sapphire Skies' is a rhizomatous plant belonging to the agave family, known for its slow growth in poor and dry soil. The species is native to the mountainous areas of central northern Mexico and is capable of withstanding temperatures as low as -16 °C (3.2 °F) in very dry soil, as well as long periods of summer drought. 'Sapphire Skies' distinguishes itself from the type species with its finer, rougher, and even bluer leaves. When young, this yucca forms a shaggy, dense, and naturally unbranched ball. After many years, it can develop a trunk, sometimes double, reaching a height of 3 to 4 m (10 to 13 ft), covered with a 'skirt' of dry leaves that can reach 30 cm (12 in) in diameter. Each trunk bears a large spherical crown measuring 1-1.5 m (3-5 ft) wide, composed of numerous linear, very rigid leaves ending in a sharp spine which one should be cautious of. The leaves are very narrow, folded in half along the midvein. They measure 40-60 cm (16-24 in) in length and 1.2-2 cm (1 in) in width. Flowering occurs after a minimum of 3-4 years of growth. In this yucca, the inflorescence is unique and partially hidden within the mass of foliage. It develops into a large, paniculate structure resembling a wide chandelier. The flowers, bell-shaped and pendulous, measure 3 cm (1 in) in diameter and have a waxy texture. They are borne on upright and branched panicles measuring 40-70 cm (16-28 in) in height and reaching over 4 m (13 ft) in height. These flowers are edible and have a slightly sweet taste, making them pleasant in summer salads. When watered during the summer, this Yucca rostrata Sapphire Skies shows spectacular growth.

Yucca rostrata Sapphire Skies requires plenty of sunlight and a very well-draining, even poor and dry soil. It especially dreads heavy, waterlogged soils in winter. It will find its place on a large dry slope, at the centre of an exotic or contemporary rockery, or even near a pool if the soil is well-prepared to receive it. It should be kept away from pathways and young children due to its sharp-pointed leaves. This large plant will be simply magnificent as a focal point, accompanied by a carpet of cistus, Cerastostigma plumbaginoides, Delosperma, or even a short grass meadow such as Korean velvet grass (Zoysia tenuifolia). It can likewise be paired with agaves, prickly pears, and hardy columnar cacti (Cleistocactus strausii, Cylindropuntia imbricata), as well as equally spectacular and frugal shrubby aloes. It can also be planted in a very large pot on the terrace. Choose the most sheltered spot, in full sun, and away from foot traffic to avoid contact with its sharp leaves.