Chilopsis linearis

Chilopsis linearis owes its nickname of desert willow to its graceful habit, the resemblance of its long leaves to those of the willow, and its desert origins. A unique tree with pink trumpet-shaped flowers in summer. It is exotic yet hardy, and remarkably understated. It is still rare in our gardens despite its numerous qualities. Graceful, original, and compact, it should quickly become indispensable for ornamenting gardens subjected to long summer droughts.

Chilopsis linearis belongs to the Bignoniaceae family, just like catalpa and red trumpet vine. It is native to semi-desert areas in the southwest United States and Mexico, where it grows in full sun in poor soil, often near dried-up watercourses, in gravel pits and on ravines. Its roots, which penetrate very deeply into the soil, allow it to withstand long months without water. Its cold resistance is around -12° C to -15° C (10.4° F to 5° F) if planted in well-drained soil. It tolerates salt spray and saline soils, as well as limestone. Its growth is slow during the establishment phase, then it accelerates.

Left to its own devices, the desert willow forms a small tree with an occasionally irregular habit, about 4 m to 5 m (13.1 ft to 16.4 ft) in all directions, carried by flexible branches. It has one or several short trunks, giving rise to rather low branching. Its deciduous leaves appear late in spring, in April-May, and fall late in autumn. They are tough, linear, narrow, tapering, recurved, and 10 cm to 20 cm (3.9 in to 7.9 in) long and 4 mm (0.2 in) wide. They are a fairly dark green. Flowering is abundant in June, and it continues sporadically throughout the summer. The flowers are arranged in conical clusters and are erect, measuring 10 cm to 30 cm (3.9 in to 11.8 in) long, at the terminal part of the branches, on the current year's wood. The flowers, about 2.5 cm (1 in) wide, are tubular and campanulate in shape, composed of 5 lobes, three of which are wider at the base and two smaller ones with highly undulate margins at the top. Their colour varies depending on the individuals, ranging from purple to dark pink, magenta, lavender blue, and white-pink, with a yellow throat or streaked with purple or aubergine. They are slightly fragrant and are pollinated by bees, especially by the large black carpenter bee. The fruits are long green pods shaped like beans, containing numerous seeds with bristles. They will be dispersed by the wind.

Chilopsis linearis is a true desert plant. Along with Red Yucca (Hesperaloe parviflora) and the dasylirions, it is one of the best plants for landscaping arid areas of the garden, from the seaside to the inland. It is not demanding on soil type as long as it is well-drained, and is perfectly drought-resistant once well-established. It is a valuable asset for dry gardens that are so lacking in summer flowers. It can be planted on its own to lightly shade a terrace, for example, or in the centre of a bed with perennials or dry soil shrubs (desert sage Leucophyllum frutescens, Salvia chamaedryoides, lavender), but away from other trees and always away from waterpipes. To accompany it, you can choose Silver Caragana (Halimodendron halodendron), Ceanothus 'Concha', or Mexican buckeye (Ungnadia speciosa), whose flowering periods are staggered. Chilopsis linearis can also be grown in a large pot to adorn a terrace.