Hosta clausa is known for its vibrant purple flower buds. It has a rhizomatous growth habit.

The foliage consists of lance-shaped leaves that are about one inch wide. They're deep green in colour with a glossy surface and a sharply pointed tip. The flower scapes, or stalks, bear numerous dark purple buds and exhibit purple dots near their base.

As a triploid hosta, this variety does not produce seeds. However, its pollen remains fertile, allowing it to participate in cross-pollination with other hosta species.