Iris pseudacorus Compact Form - Yellow Flag

The Iris pseudacorus ‘Compact Form’ is a marsh iris with moderate growth. This selection has the clump-forming foliage and golden yellow flowers of the type species, but its leaves are finer and its flower stalks shorter. The plant takes up less space on a bank or in a small pond. It blooms in spring. Plant this water iris in moist soil or in an aquatic basket.

This variety is a perennial plant with fleshy rootstocks from the Iridaceae family. It is a compact form of the Iris pseudacorus, the yellow iris of banks, ditches and marshes. The type species grows naturally from Europe to the Caucasus, around the Mediterranean and as far as Iran. In France and elsewhere, it is found in waterlogged ground, reed beds, near ponds and along the banks of slow-moving streams. It grows from thick rootstocks capable of surviving in heavy, oxygen-poor soil. The foliage of the marsh iris is deciduous to semi-evergreen depending on the winter.

In ‘Compact Form’, the vegetation forms a clump that is lower and finer than that of the type species. The flower stalks measure between 50 and 70 cm in height. After 3 or 4 years of cultivation, the plant occupies 30 to 40 cm in width. The rootstocks advance around the periphery of the stump without producing suckers. On a natural bank, the clump gradually thickens. In a small pond, an aquatic basket helps contain the rootstock and makes it easy to lift the plant for division. The leaves are erect, narrow, bright green to glossy green. The flowers open in May-June, sometimes until early July in cool climates. They are smaller and lighter than those of the wild marsh iris, but have the characteristic silhouette of water irises: three large trailing sepals, three narrower erect petals, and petaloid stigmas in the centre. Their golden yellow colour is almost uniform. 
The name pseudacorus means 'false sweet flag': the leaves resemble those of the Acorus calamus, another bank plant, although they do not belong to the same botanical family.

Plant Iris pseudacorus ‘Compact Form’ at the edge of a pond, on a bank or in a border that never dries out in summer. You can associate it with other bank plants such as Caltha palustris var. alba, Primula rosea ‘Grandiflora’, Lobelia siphilitica ‘Alba’ and Iris sibirica (sanguinea) 'Snow Queen'.