Carex berggrenii

Carex berggrenii is a miniature and evergreen sedge that forms a very low tuft of grass-like foliage beautifully coloured from bronze to copper brown throughout the seasons, with a slight metallic sheen. This small grass spreads very slowly, forming a small ground cover adorned with short brown spikes, and remains attractive throughout the year, even in winter. Hardy and undemanding, this lovely perennial plant will thrive in fresh rock gardens or bordering flower beds, in well-drained but moist soil, in full sun or partial shade.

Carex berggrenii is a rhizomatous perennial from the Cyperaceae family. It is native to New Zealand. This species grows in subalpine mountain areas. It thrives in cool and sunny locations in nature, and is highly resistant to frost (down to -18°C (-0.4°F)). It adapts to any well-drained soil without excessive limestone content. Its foliage consists of almost flat ribbon-like leaves, 3 to 6cm (1 to 2in) long and 1.2 to 3mm (1in) wide, with very distinct veins and a slightly glossy appearance. They emerge in a fern-green to olive-green colour and quickly turn bronze. They are clustered in a very dense tuft that will not exceed 5cm (2in) in height. It slowly expands to form a low cushion about 30cm (12in) wide. In cold weather, the leaves take on dark purple-red, burgundy red, or orange-red tones that are very decorative. The inconspicuous flowering occurs from March to July. It takes the form of short brown floral spikes 20cm (8in) long. This evergreen sedge retains its beautiful foliage in winter. Its colours will be more intense if it is exposed to full sun. 

Carex berggrenii is an unusual border or rock garden plant, and is particularly pleasant in alpine troughs. It will thrive near a small pond or stream, as long as the soil is not constantly waterlogged. It can also be planted in groups of 5 to 10 specimens on the edge of cool woodlands or in the design of a living wall. Where it is happy, this sedge will form unique and highly decorative ground covers. It can be combined with other ground cover plants that appreciate similar conditions, such as small ferns (Polypodium), other small carex, saxifrages, and Ophiopogon. However, be sure to plant its neighbours at a respectable distance to avoid suffocating it.