Digitalis purpurea (foxglove)

Japanese name: ジギタリス
Scientific name: Digitalis purpurea

[Overview]
A biennial to perennial that can reach as much as 2 m tall.
Because it has weak heat tolerance, in horticulture it is often treated as a biennial sown in autumn.
The species is highly variable in form.
The whole plant is hairy.
There are basal leaves and stem leaves; the basal leaves are ovate to lanceolate with long leaf stalks.
The stem leaves are alternate, and those in the upper part of the stem have short stalks or none.
A long raceme at the stem tip bears many flowers biased to one side, and the flower spike blooms from the bottom up.
The flowers are bell-shaped, 4–7.5 cm long, with a shallowly 4-lobed two-lipped tip, and hang downward.
The flowers are reddish purple, pink, white and so on, with dark purple spots edged in white inside.
The fruit is a capsule.

[Uses]
It is highly poisonous, but is also well known as a medicinal herb.

[Cultivation]
Propagate from seed, by division, or by stem cuttings.
It does not flower unless a plant of a certain size has been exposed to winter cold, so spring-sown plants flower the following year and autumn-sown plants the year after that.
The optimum germination temperature is 20–25°C, and germination takes about 10 days; the seeds need light to germinate, so sow them on seed-sowing soil without covering them with soil, and water from the bottom so the soil does not dry out.
It prefers fertile soil with sun, good drainage and good aeration.
Transplanting is easy.
Water thoroughly when the soil surface dries.
Apply slow-release chemical fertilizer as a base fertilizer, and give additional fertilizer in spring.
When the flowers have bloomed up to the top of the spike, cut the flower stalk at the base, and side shoots will grow to give a second bloom.
If you are not collecting seed, cutting the flower stalk keeps the plant from becoming exhausted.
Aphids can occur.

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