Trachelium caeruleum (blue throatwort, "Yugiriso")

Japanese name: ユウギリソウ （夕霧草）
Scientific name: Trachelium caeruleum

[Overview]
A perennial about 1.2 m tall, but because it is sensitive to heat and humidity, it is treated as an annual or biennial in Japan.
The whole plant is hairless.
The stem is erect.
The leaves are simple and alternate, ovate to lanceolate, about 8 cm long, with toothed or doubly toothed margins.
Corymbs at the stem tips bear many small flowers densely.
The flowers are salverform with a long tube, the tip is 5-lobed, and the long style protrudes out of the flower.
The flowers are usually bluish purple, but there are also cultivars in white, reddish purple, pink and other colors.

[Cultivation]
Propagate from seed or by cuttings.
When growing from seed, the seeds are minute, so use sowing soil and a tray, do not cover them with soil, and water from below.
Transplant to the final position when 5–6 true leaves have formed.
It prefers a sunny, well-ventilated, well-drained place.
For potted plants, water thoroughly when the soil surface dries; for plants in the ground, rainfall is sufficient.
Once flower buds rise, take care not to wet the inflorescence.
From transplanting until flowering, apply diluted liquid fertilizer.
Pests and diseases include damping-off, gray mold, aphids, armyworms and red spider mites.

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