Symphytum officinale (common comfrey, "Hirehariso")

Japanese name: ヒレハリソウ （鰭玻璃草）
Scientific name: Symphytum officinale

[Overview]
A perennial that reaches 1 m in height, found in slightly moist places such as near houses and in pastures.
It has thick roots.
The whole plant is covered with coarse white hairs and feels rough.
There are basal leaves and stem leaves, and the basal leaves have long petioles.
The stem leaves are simple and alternate, oblong, with entire margins.
The leaf base runs down the stem to form wings.
Cymes at the top of the stem bear purple to white flowers that hang downward.
The corolla is bell-shaped with 5 shallow lobes at the tip.

[History]
It was introduced in the Meiji era and has become naturalized in various places.

[Uses]
It was formerly used as food and as a health food, but it is now the subject of notices advising people to avoid consuming it because it causes liver damage.

[Cultivation]
Propagate by division or root cuttings.
It prefers sun to partial shade and slightly moist, water-retentive soil.
If the conditions suit it, it grows well even when left alone.
Even for plants in the ground, water in midsummer when the soil surface dries so that it does not become too dry, and do so in the morning or evening when temperatures are low.
Fertilize sparingly; if base fertilizer is applied, none is particularly needed.
There are no particular pests or diseases.

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