Sequoiadendron giganteum Glaucum

Sequoiadendron giganteum 'Glaucum' is a variety of giant Sequoia. Smaller than the natural species, this conifer remains nevertheless a majestic tree, reserved for large gardens. It is distinguished by its foliage and branches with intense greyish-blue reflections. For many years, it grows more in height than in width, showing a narrow pyramidal habit, supported by a very vertical main trunk, whose reddish-brown bark cracks into deep grooves. It widens with age, extending its drooping branches in a graceful movement that guides them towards the sky with their tips. It adapts to any well-drained and rather fertile soil, prefers humid climates, but hot in summer.

Sequoiadendron giganteum is a conifer of the Taxodiaceae family, native to North America, specifically the southern slopes of the northern Sierra Nevada mountains in California. Fossils attest to the presence of Sequoias in Europe before the major glaciations of the Quaternary period. In its natural environment, under good conditions, it will reach a height of 50 to 85 metres (164 - 278ft) with a span of 8 to 10 metres (26 - 33ft), and will develop a massive pyramidal habit. This species shows fairly rapid growth, it appreciates cool and rainy climates, hot summers, and snowy winters that offer excellent protection to the roots and young plants.

The 'Glaucum' variety is a more modest form of this species, introduced in Germany in 1870. This conifer of great ornamental value also differs by the magnificent colouration of its foliage and young branches, in grey-blue. It initially shows a narrow conical pyramidal habit, then widens after many years. Its growth is quite rapid; it will reach a height of 30 to 40 metres, and 8 metres in span at maturity. Its main branches are slightly drooping, straightened at their tips, covered with narrow and triangular, pointed needles, measuring 1 to 1.2cm (0.4 - 0.5in) long, reminiscent of those of cypresses. On the young branches, with blue-silver bark, they measure between 0.3 and 0.6cm (0.1 - 0.2in). This plant is monoecious, meaning there are male and female individuals. When the female cones are pollinated, they take on an ovoid shape, a reddish-brown hue, and an upright posture. They mature in two years. The bark of this Sequoia is remarkable, both for its reddish hue, its fire resistance, and the deep decorative crevices that form over the years. This plant has a very developed but rather shallow root system, which makes transplantation a bit delicate, but allows it to draw on the soil's nutritional and water resources with great opportunity.

Sequoiadendron giganteum 'Glaucum' will be planted in a garden large enough to accommodate it. If the conditions are met, it will be an exceptional tree, which will make the gardener who planted it proud, it will undoubtedly outlive him, fully integrating the history of a family and a garden. It can be planted as a focal point, or as a hedge at the edges of the countryside, placed in front of a curtain of Phyllostachys bambusoides, the giant bamboo. Such a massive tree demands a solid base; its location should be carefully chosen, in deep soil and in a well-cleared situation. It requires little or no maintenance after the first few years, and goes well with large stones, the geometric lines of swimming pools, and masonry works. The real graphic qualities of conifers naturally impose themselves in the design of a contemporary garden, which prefers the aesthetics of forms, silhouettes, and textures to the waltz of flowering plants. These plants with their reassuring permanence structurally and durably shape a flowerbed, mark the paths, border the terrace, easily replacing the strong presence of trimmed boxwood or holly. The key is to play with volumes and colours.