Easy-to-grow Scabiosa must be one of the prettiest garden flowers. Growing in small clumps, the flowerheads stand above the foliage, gently moving with the slightest breeze. On warm summer days, butterflies are often seen on the flowers, for Scabiosa is one of their favourite nectar plants.
The Dipsacaceae or Scabious family is found in Africa and Asia, but is most abundant in the Mediterranean region where there are 11 genera and 290 species. Two genera are indigenous to southern Africa, Cephalaria and Scabiosa. In South Africa there are nine species of Scabiosa; in total there are 100 species distributed from Africa to Asia.
The Scabiosa genus is large and so plants grown in the garden may be hardy annual, half hardy annual, hardy biennial or Hardy perennial in nature.
Scabiosa range in height from 15 to 60cm. They bloom from Summer through to the first months of autumn, and carry domed flowers of white, blue, purple, red or yellow atop long stems. As they are often mat forming they make ideal plants for use in garden borders.
Some of the more common names for Scabiosa include, Scabious, Sweet Scabious, Pincushion flower and Mourning-bride.
The timing of the sowing of Scabiosa depends on their nature. Annuals are usually sown after the last frost, perennials may be sown at the start of spring or autumn. Scabious seeds should be lightly covered once sown and spaced at about 30 to 40cm apart. They like to grow in sunny areas that have good drainage. Ideally the soil that Scabious grows in should be humus rich, slightly alkaline (pH 7 to pH8) and moist.
The germination of Scabiosa seeds usually takes about two weeks, and can be done indoors at a temperature of 20 to 25oC. If growing indoors first then sow annuals 5 weeks in advance and perennials about 10 weeks in advance. Transplant annual Scabiosa following the last frost, and perennial varieties in late autumn or before the last frost.
Mass plant Scabiosa to form a groundcover, or position smaller clumps on a rockery. Use it to provide a splach of colour in a townhouse garden or as an edging plant along the front of an informal border.
The combinations for Scabiosa with other plants are limitless, for it can be used with spring annuals, summer perennials or in a bed as a fast-growing groundcover and colour filler. In a perennial border Scabiosa combined with Vernonia glabra, Geranium multisectum, Agapanthus and Orthosiphon labiatus, forms a lovely show for summer. Scabiosa can also be planted with succulents — a striking combination is Scabiosa with the grey leaf form of Cotyledon orbiculatum (pig’s ears).
CARING FOR SCABIOUS
It is easy to look after members of the Scabiosa genus such as Scabious and Pincushion flower; they should be staked in windy areas, as they have delicate wiry stems; keep the soil moist in summer; deadhead flowers once they have finished blooming; cut the Scabiosa plants back at the end of the growing season in autumn. It is necessary to divide the plants every two or three years to maintain vigorous growth. If you require more plants then divide perennial Scabiosa at the start of spring, or take cuttings in the summer time.
The plants can be fed every 8 weeks with slow-release 3:1:5 fertiliser.
FOR SOUTH AFRICAN GARDENERS
Those southern African gardeners wanting to stay true to the indigenous here are brief profiles of the two best known species found here
This is the species most often seen in South African gardens. Scabiosa africana grows fast, forming evergreen mounds of velvety leaves. Many thick stems shoot from the ground, bearing large rosettes of light green leaves. These big, soft and hairy leaves are oval shaped, about 160 mm long and 50 mm wide, with ruffled edges. From the leaves, the stems grow almost 1 m longer, dividing into side branches with the typical scabious flowers at the tips.
Flowering from spring to early summer, the plants are a beautiful sight with the many tall flowering stems waving in the wind. Looking at the flowers closely, one realizes that each head, which is about 50 mm across, is made up of many smaller flowers that vary in shades of mauve and white. After flowering, the heads turn into tight, bristly balls that fall apart as the seeds ripen.
Scabiosa africana is easy to grow in the garden and is a long-lasting cut flower. It requires full sun to semi-shade and good garden soil mixed with compost. New plants grow fast, flowering usually within their first year. Older plants tend to get untidy, but cut the old long woody stalks right back after flowering. This will encourage the plant to make many new shoots from the base. The plants tend to seed themselves quite happily in the garden.
New plants can be propagated from seed or cuttings. The seeds are inside the dried flowers and look like little badminton shuttlecocks. The seed can be sown in autumn or spring and will take about 3 weeks to germinate. The seedlings transplant easily and are hardy to winter cold. Cuttings can be made of new shoots from the bottom of the plant. Remove most of the big leaves and treat with a rooting hormone like Seradix.
For the garden, the different forms of Scabiosa incisa are much more vigorous and exciting. Growing naturally on the coastal sands from Bokbaai to Grahamstown, it gives a spectacular show in spring with its large deep pink to mauve and white scabious flowers.
A fast-growing perennial, it forms a number of stems on the ground, which turn slightly woody with age at the base. The finely divided leaves form opposite each other along the lower part of the stems. The older leaves at the bottom of the stem turn brown and fall off as new fresh green leaves are formed.
The soft leaves are slightly hairy at the top and bottom. The beautiful flowers are formed on long, naked stems from early spring to the middle of summer (September-December). The straggling stems vary in height but can stand up to 430 mm high with a single flower head at the tip.
A closer look at a flower reveals individual flowers that are crowded together to form dense, flattened flower heads. The looser flowers along the outside have longer petals that form a frilly edge, whereas the flowers in the centre are much smaller and compact to form a tight button effect. After flowering, the seeds are formed in interesting rounded bristle heads, that slowly fall apart as the seeds ripen and are ready to be blown away by the wind.
The best-known locality for Scabiosa incisa is at Bokbaai, a farm along the West Coast, from where one has the most beautiful views of Table Mountain across the bay. Here S. incisa grows in deep sands between the coastal scrub. The winter rainfall along this part of the coast is between 50 to 300 mm a year. S. incisa from Bokbaai is a particularly big form with large, mauve flowers.
Scabiosa incisa ‘White Carpet’ has a smaller white flower which in early summer form a cloud of white above a lush carpet of tight green foliage.
For photos and cultivation information on hundreds of Southern African indigenous plants, you can also visit www.PlantZAfrica.com .