Plantago princeps var. laxifolia is a small shrub with hollow, erect, or ascending stems, growing approximately 15–250 cm in length, branching, and featuring young internodes that are ± woolly with reddish-brown hairs. The leaves are tufted near the stem tips, forming thick, coriaceous structures with narrowly oblong-lanceolate to narrowly elliptic or sometimes elliptic blades, measuring 10–30 cm long and 1.5–5 cm wide. These leaves transition smoothly from the petioles, with an acute to acuminate apex and a base either slightly narrowed and sessile or gradually attenuating to a winged petiole. The leaf surfaces are glabrous or sometimes appressed pilose on the lower side, with minutely and remotely denticulate margins or smooth. The leaves have (3–)5–9 veins that converge towards the base. Petioles can extend up to 5 cm and are winged, while stipules are absent. The flowers occur as scapes, typically multiple, ranging from 10 to 50 cm in length, with spikes (7–)11–28 cm long that are glabrous to sparsely pilose. The flowers are densely packed, sometimes resulting in an interrupted spike formation, each protruding at nearly a 90° angle from the axis. Bracts are lanceolate, 1.2–3 mm long, either glabrous or sometimes woolly at the base, with bracteoles missing. The flowers are bisexual (perfect), with a calyx comprising four sepals, elliptic to elliptic-ovate, 1.8–3.2 mm long, scarious except along the midrib, either glabrous or ciliate. The corolla is salverform with four lobes, remaining throughout the fruiting period, covering the upper part of the capsule, and the lobes spread out, measuring 1.5–2 mm in length. It has four stamens, alternating with the corolla tubes, filaments fused to the corolla tube, and long-exserted, dithecal anthers opening longitudinally. The superior ovary is 2-carpellate, apparently with two to four ovules and axile placentation. The fruit is a narrowly ovoid-ellipsoid capsule, 3–3.8 mm long, slightly protruding from the calyx, and opening at a point two-thirds to the base or slightly more. It contains three to four black ellipsoid to oblong-ellipsoid seeds, 1.5–2.1 mm long, covered with a mucilaginous membrane and a well-developed, firm, translucent endosperm. It occurs on steep slopes, rock walls, or at the bases of waterfalls, at elevations between 480-1,100 meters.