Yucca aloifolia

Yucca aloifolia, sometimes called Aloe Yucca or Spanish Dagger due to its sword-shaped leaves armed with a formidable spine, is a shrub native to the desert areas of Mexico that brings a highly exotic quality to the garden while tolerating our winters quite well. With relatively rapid growth for its genus, this yucca forms rosettes at the top of a short trunk, branching out with age, with large stiff and tough dark green leaves. Its summer flowering is spectacular, and its warlike appearance works wonders on a large arid slope. A steep pathway lined with its tall white-pink spikes has a certain regal charm to it.

Native to the southeastern United States, or more precisely a thin coastal strip bordering the northern Gulf of Mexico and the southeast of the United States, Yucca aloifolia is capable of withstanding temperatures of around -14 °C (6.8 °F) in dry soil, as well as long periods of summer drought. It is a rhizomatous plant belonging to the agave family. When young, Yucca aloifolia forms a shaggy ball, naturally sparsely branched. After many years, it can develop a trunk 3 to 6 m (10 to 20 ft) tall and 12 to 15 cm (5 to 6 in) in diameter, slightly swollen at the base, with few branches. In our temperate climates, the plant will reach 3 to 4 m (10 to 13 ft) in all directions when in bloom, with a foliage height of 2 m (7 ft). The tough leaves are arranged in a rosette. They are 50 cm (20 in) long and 3-4 cm (1-2 in) wide, rigid and lanceolate with a pointed blade shape. Flowering occurs after 3 to 4 years of growth. In this species, the terminal inflorescence does not necessarily result in the division of the rosette that carries it. The flowers, bell-shaped and pendant, measure 5 cm (2 in) in diameter and are pure white with a wash of pink at the base of the petals. They are carried on upright and branched panicles measuring 50 to 80 cm (20 to 32 in) in height, and reaching over 3 m (10 ft) in height. This yucca is the only one capable of producing fruit in our temperate climates: they are fleshy, edible, have the appearance of small violet-pink aubergines, and their flavour resembles that of blackcurrants to some palates. The plant produces a few offshoots, forming a small cluster of trunks after a few years.

Yucca aloifolia will thrive in any well-drained soil, even if it is dry and poor. It should be kept a little distance from pathways and young children, due to its dangerously pointed leaves. This large plant is ideal for structuring a large rockery, or for brilliantly occupying the centre of an exotic bed. It can be planted as a standalone specimen or combined on an arid slope with Puya caerulea, Agave americana, prickly pear cactus, hardy columnar cacti (Cleistocactus strausii, Cylindropuntia imbricata), and equally undemanding Canary Island viper's bugloss. Aligned behind a small hedge of myrtle, Westringia, rosemary, Pittosporum, Myrsine africana or boxwood, it can create a beautiful defensive background on the garden's edge. It can also be planted in a very large pot on the terrace, right next to a banana tree, carefully choosing the most sheltered spot, in full sun, and away from foot traffic to avoid contact with its sharp leaves.