Scutellaria scordiifolia

Scutellaria scordiifolia, also known as helmet skullcap, is a perennial related to mints, better known for its use in herbal medicine than in ornamental gardens, despite its ease of cultivation in any well-drained, moist to dry soil. It forms a low, spreading clump, from which a good number of spikes of long flowers of an intense gentian blue emerge in late summer. Vigorous, hardy, and able to withstand root competition, it thrives in sunny borders and rockeries. It  also makes lovely potted displays.

Scutellaria scordiifolia is an herbaceous, rhizomatous perennial belonging to the Lamiaceae family, along with sage, mint, and thyme. It is native to the open, humid areas of China and Siberia. It is found in deciduous forests, pine forests, marshy meadows or grassy slopes, at an altitude of 2100m (6890ft). It is a perfectly cold-hardy plant, also able to withstand periods of relative drought.

The plant shows a moderately fast growth rate and will not exceed an average of 20cm (8in) in height (for foliage) with a 50 to 60cm (20 to 24in) spread. The stems are produced by a shallow stoloniferous underground stem with small tubers that act as a food reserve in case of difficult periods, such as drought. The stems are purple, slightly hairy, rough, and curved at the tip, with a square cross-section. They have opposite leaves towards their basal part, separated along the stem by long internodes. The light green linear to triangular leaves are 1.5 to 3.8cm (1 to 2in) long and 1 to 1.4cm (1in) wide. Their surface is hairy and their margin serrated. The stems, erect up to 50cm (20in) from the ground, produce numerous flowers in groups of 2 to 4 in the leaf axils from June to August. The small flowers, 1.5 to 2cm (1in) long, are generally tubular and bilabiate. They have a violet calyx enclosing two lips, the upper of which is helmet-shaped. Their colour is a bright gentian blue, slightly marked with white at the throat. The flowers are popular with pollinating insects. Its vegetation dies down in winter and returns at the end of March.

This skullcap is an adorable little plant. It is floriferous and easy to grow in well-drained soil. It is often used in rock gardens that are not too dry, or at the edge of paths or beds that it festoons with its very blue blooms for several weeks in summer. Withstanding the competition of shrub roots, it will also find its place at the foot of a hedge, as long as it receives sunlight there. It can be planted with, for example, helianthemums and sedums. It can also be placed near a pond, as long as the soil is not waterlogged. It can be easily grown in pots, to decorate a patio or balcony during summer.