Salvia plectranthoides: is a small herbaceous clumping perennial from Asia with pinnate leaves and pale blue flowers 30-60cmH in spring and summer.
Salvia plectranthoides: is a very attractive small clumping plant that would normally grow on the forest floor.
Flowers: small, pale blue, semi tubular but falcate in shape. The hood is small, rounded and straight, slightly hairy, pale blue, often with a white tip, which is an indicator to insects flying above that flowers are open and ready.
The 2 side lobes, also pale blue and white are flared out to help open the throat area. The middle lobe is long, wider at the end and is either cupped to hold a drop of moisture and indicates that the flower is fresh and ready for an insect to visit, or the lobe is drooping downwards, indicating that the flower has been visited.
A large white area is found around the throat with pale blue markings to guide the insect further into the corolla.
Flowers are held on many stems in whorls of 4-8 flowers in regular intervals along a green flower stem until the last flower is reached at the top.
Inflorescences are usually in a panicle formation, with a central stem and a few side shoots. Stems can be up to 60cmH, all with the flowers being at the top half of the stem, well above the foliage to attract passing insects.
Calyces: are primarily green, but may colour up to a purple/ brown colour if grown in a sunny position, but in dapple shade, they remain green. All lobes are ribbed and flared out at the tip to allow the corolla max space to open fully.
All the calyces in the whorl face down in a candelabra manner with the flower opening out and upwards to receive the insect.
Calyces remain on the stem after the flower has finished, turning brown with age, whilst holding small dark seeds. These can be disbursed when the stem is knocked or shaken.
Leaves : are a dark green, pinnate in formation with usually 5-7 lobes and a terminal lobe. These form a loose basal clump while the flower stems rise well above. All lobes are thin textured, lanceolate to cordate, a pointed tip and crenations along the margins.
Salvia plectranthoides: normally grows on the forest floor in a woodland setting in dappled shade or a sunny well protected position. A wonderful sight when in flower if grown under a deciduous tree en masse. Even when not in flower, the dark green clumps look inviting.
This Salvia can be grown in a mixed border with other woodland perennials which like similar growing conditions. They also make very good plants to edge a pathway and so easily grown, they may even seed a little These can be used to expand the clumps under the trees.
Because they grow best in a woodland environment, they do like mulch, additions of humus and compost at the beginning of the season and a little extra water during the hot dry summer season. Once established they can be quite hardy, enjoying the cold rainy days, but not the frosty cold weather. It is then that the plants begin to go down over the very cold frosty period.
When flowers have finished, seed collected, stems should be cut down, any debris cleared out and the crowns mulched and marked with a marker – so the area is not trodden upon or accidentally dug up.
In late winter, early spring just as the leaves are appearing, feed well with humus and compost, then mulch well to keep the root area cool over the hot dry season.
Propagation: usually by seed sown in spring or by taking side shoots in summer. Clumps, if large enough might also be divided.