Cautleya lutea is a perennial herbaceous member of the ginger family that produces summer flowers. Native to the Himalayas, south China and Vietnam, it suits cooler, shaded sites. It prefers partial shade in moist, well-drained soil and carries a UK hardiness rating of H5 (hardy). Flowering occurs from July to September.

Hidden Ginger (Cautleya lutea) is a perennial ginger for partial shade in moist, well-drained soil, flowering July to September.

https://en.wikipedia.org/wiki/Cautleya_gracilis

Cautleya is a small genus of perennial plants of the family Zingiberaceae, found in the eastern Himalayas through to China and Vietnam. It consists of two species of high-altitude tropical and temperate plants, native to cool forest areas – an unusual habitat for members of the Zingiberaceae.

Cautleya lutea

Hidden Ginger | Cautleya lutea

Cautleya robusta is a perennial herbaceous member of the ginger family native to the Himalayas and Yunnan. In UK gardens it flowers from July to September. Plants in the genus form layered leaf bases that give a stem-like appearance and produce a summer spike of flowers. Growers prize it for its seasonally concentrated display in midsummer.

Cautleya robusta is a perennial herbaceous ginger from the Himalayas and Yunnan that flowers in the UK from July to September.

https://en.wikipedia.org/wiki/Cautleya_spicata

Cautleya robusta

Cautleya spicata is a perennial herbaceous member of the ginger family that flowers July to September. Native to the Himalaya, it typically reaches about 1.0 m. It favours full sun and a moist but well-drained sandy to loamy soil. Its H5 rating identifies it as hardy for most UK gardens.

Himalayan Ginger (Cautleya spicata) flowers July to September, grows to 1.0 m and prefers full sun with moist, sandy to loamy soil.