Eustoma grandiflorum (Eustoma, "Torukogikyo")

Japanese name: トルコギキョウ
Scientific name: Eustoma grandiflorum

[Overview]
An annual, biennial or short-lived perennial.
The whole plant is grayish green.
The leaves are simple, basal or opposite, thick and fleshy, ovate to oblong, with entire margins.
The leaves on the stem are stalkless, and the bases often clasp the stem.
The flowers are borne singly in the axils of the upper leaves, or in paniculate inflorescences.
The corolla is bell-shaped, deeply divided into 5–6 lobes, and blue to white, but in garden cultivars the flower colors are varied and there are also double-flowered forms.
The stigma of the pistil is divided into two lips, and there are 5–6 stamens.
The flower stalks are long.
The fruit is a capsule.

[History]
It was introduced to England around the 19th century.
The genus name at first was Lisianthus, so it is still sometimes called by that name today.
It was introduced to Japan during the Showa 10s (1935–1944), and breeding was carried forward.
Today almost all cultivars have been developed in Japan.
There are various theories about the origin of the Japanese name Toruko-gikyo, some based on the flower color and others on the flower shape, but nothing is certain.

[Cultivation]
It prefers fertile, humus-rich soil that is sunny and well drained.
It dislikes humidity.
During flowering, apply liquid fertilizer about once a week.
Remove spent flowers promptly to prevent exhaustion of the plant and the occurrence of disease.
After the flowers have all finished, cut the plant back hard, leaving 3–4 nodes from the base, and side shoots will emerge to give a second flowering.
Temperature control is difficult when raising seedlings from seed, so it is more common to buy flowering seedlings and grow them.
Sow in September–October.
The seed is very fine and needs light to germinate, so sow it on seed-sowing soil without covering it with soil, and water from the bottom so the soil does not dry out.
Germination requires a temperature of about 25°C, but keep it at around 15°C while raising seedlings.
In winter, protect it from freezing.
After raising the seedlings, plant them out in March–May.
Until the flower buds elongate, water thoroughly when the soil surface begins to dry.
Diseases and pests include gray mold, aphids, armyworms, diamondback moths and slugs.

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