Yucca rigida Blue Sentry

Yucca rigida Blue Sentry features a columnar habit and bluish foliage and is one of those extraordinary plants from the North American deserts that we dream of adopting to break the monotony of our landscapes and bring them the breath of the great outdoors. With a beautiful stature, it develops a thick trunk topped with a superb column bristling with bright leaves finely edged in yellow. Over time, the plant produces a large inflorescence filled with cream-white flowers. Give it a prime location in a dry garden or at the centre of a large rockery as it truly deserves it! 

Native to the mountainous areas of central northern Mexico, Yucca rigida is able to withstand temperatures around -15 °C (5 °F) in dry soil, as well as long periods of summer drought. Like other Yuccas, it is a slow-growing rhizomatous plant belonging to the agave family. The Blue Sentry cultivar was recently selected for its more slender habit and even more decorative foliage. When young, this yucca forms a very dense, shaggy mass. After many years, it develops a trunk covered with a 'skirt' of dry leaves, reaching up to 30 cm (12 in) in diameter. This trunk bears a large crown, 1 to 1.5 m (3 to 5 ft) wide, composed of a multitude of rigid leaves. The trunk and crown together can easily reach a height of 3 m (10 ft). The leaves, very blue when they emerge, turn into a soft blue-grey finely edged with pale yellow. They are stiff, measuring 40 to 60 cm (16 to 24 in) in length and 1.2 to 2 cm (1 in) in width, and are terminated by a strong spine. Flowering occurs after 4 to 6 years of growth. In this yucca, the inflorescence is unique and partially buried in the mass of foliage. The flowers, bell-shaped and 3 cm (1 in) in diameter, are cream-white and have a waxy texture. They are arranged in upright and branched panicles measuring 50 to 80 cm (20 to 32 in) in height, and borne at a height of over 4 m (13 ft). When watered during the summer, this Yucca rigida shows spectacular growth.

Yucca rigida Blue Sentry requires plenty of sunlight and a very well-draining soil, and even poor and dry but preferably limestone soil. It particularly fears heavy soils that are waterlogged in winter. It will find its place on a large arid slope, at the centre of an exotic or contemporary-style rockery, or even near a swimming pool if the soil is well prepared to accommodate it. It should be kept away from walkways and young children due to its sharp-pointed leaves. This large plant will be simply magnificent when isolated, emerging from a carpet of cerastiums, Cerastostigma plumbaginoides, Delosperma, or even a dry meadow lawn such as Korean velvet grass (Zoysia tenuifolia). It can likewise be combined with agaves, prickly pears, and Dasylirions, which are equally spectacular and frugal. It can also be placed 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.