According to The Genus Hosta by W. George Schmid (1991), as the name implies, it has a very distinct, upright (erect) form to the clump. H. rectifolia is related to the species H. sieboldii.

The glaucous leaves are dark green to blue-green in color. It grows into a large size hosta about 24 inch high by 70 inches wide. The leaves have stout petioles and are lanceolate in shape, flat and have smooth texture. This species bears striped, purple flowers with purple anthers from mid-August into September. There are short green bracts on the flowers scapes.

From the Field Guide to Hostas by Mark Zilis (2014), "Many variegated forms of H. rectifolia exist, most found in the wilds of Japan."

The New Encyclopedia of Hostas by Diana Grenfell (2009) describes H. rectifolia as: "A broad-spectrum species with many attractive variegated forms not yet in commerce. The scapes are known to tower over 7 ft. (2.1 m), a characteristic that could more often be exploited in hybridizing programs."

Mark Zilis' Field Guide to Hostas (2014) states that this species was found in Japan in "...swamps; wetlands; woodlands..."

Mikiko Lockwood in an article on The Hosta Library titled, A Little About Japanese Hosta Terms defines the term tachi as upright, 'Tachi Gibōshi' or H. rectifolia.