[Overview]
A perennial.
Some are evergreen and some go dormant.
It has tubers, and the roots are thick and fleshy.
All the leaves are basal, linear to lanceolate.
An umbel at the tip of a long flower stalk bears blue, purple, white and other flowers.
In some the tip of the corolla opens, while in others it opens little and the flowers face downward.
The fruit is a capsule.
[Cultivation]
Propagate by division, from seed, or by shoot cuttings.
Divide after flowering so that each clump has about 3 buds.
Evergreen types die back above ground when temperatures fall below -5 degrees in winter.
In a sunny, well-drained place it grows well regardless of soil type.
It tolerates dryness well; for potted plants, water thoroughly after the soil dries, and for plants in the ground, rainfall is sufficient.
If base fertilizer is applied, no further fertilizer is particularly needed, but for potted plants, slow-release fertilizer may be placed on the soil in spring and autumn depending on growth.
If you are not collecting seed, cut off the flower stalks after flowering so that the plant does not become exhausted.
Aphids can occur.
