Sequoiadendron giganteum

The Sequoiadendron giganteum, also known as the American giant sequoia, should not be confused with the Metasequoia, which is smaller and of Asian origin. This iconic conifer from the western slopes of the Sierra Nevada in California is famous for its phenomenal size and longevity.  For many years, it grows taller than it does wide, displaying a narrow pyramidal habit supported by a massive, upright trunk with deep, reddish-brown fibrous bark. It expands with age, extending its trailing branches in a graceful movement that guides them towards the sky. A true botanical monument, it requires a garden large enough to accommodate its massive growth, especially considering it will outlive many generations of gardeners!  

The Sequoiadendron giganteum is a conifer of the taxodiaceae family, native to North America, specifically the humid slopes of the Sierra Nevada mountains in California. Fossils indicate the presence of sequoias in Europe before the major glaciations of the Quaternary period. In its natural habitat, under favourable conditions, it can reach a height of 50 to 85 m (164 to 279ft) with a spread of 8 to 10 m, developing a massive pyramidal habit. This species exhibits fairly rapid growth and thrives in cool, rainy climates, with hot summers and snowy winters that provide excellent protection for its roots and young plants.

This highly ornamental conifer initially displays a narrow, conical pyramidal habit, which widens after many years. Its main branches are slightly trailing, with upright tips, covered in narrow, triangular, sharp needles measuring 1 to 1.2 cm (1in) in length, resembling those of cypresses. On young shoots, they measure between 0.3 and 0.6 cm (1in). This plant is monoecious, meaning it has both male and female parts. When the female cones are pollinated, they become ovoid, reddish-brown, and upright. They mature in two years. Its trunk is a colossal pillar that takes on a fascinating appearance over time. The bark of this sequoia is remarkable, with its reddish hue, resistance to fire and fungal attacks, and the deep burls and decorative cracks that form with age. This plant has an extensive but surprisingly shallow root system, making transplantation somewhat delicate, but allowing it to draw on the soil's nutritional and water resources. This characteristic also makes it vulnerable to strong winds, especially in loose soil.

The Sequoiadendron giganteum should be planted in a garden large enough to accommodate it. Under suitable conditions, it becomes an exceptional tree that will make the gardener who planted it proud, and will undoubtedly outlive them, becoming a part of a family's and garden's history. It can be planted as a focal point or as a hedge at the edge of the countryside, placed in front of a curtain of Phyllostachys bambusoides, the giant bamboo. Such a massive tree requires a solid base; its location should be carefully chosen, with deep soil and a well-exposed but sheltered position to prevent it from being toppled by the wind. It requires little to no maintenance after the first few years and pairs well with large stones, geometric pool designs, and masonry works. This legendary tree also finds its place in contemporary or exotic-inspired gardens.