About Buddleja utahensis Coville
Buddleja utahensis is a compact, dwarf dioecious shrub that grows 0.3 to 1.0 meters tall. Its bark is greyish and rimose, and the plant is defined by its persistent bare twigs. Younger branches are terete, and carry subsessile leaves that range in shape from linear to oblong. The leaves measure 1.5โ3.5 cm long and 0.3โ0.5 cm wide, with rounded apexes and attenuate bases. Both leaf surfaces are covered in dense short tomentum, which gives the plant an overall silver-grey appearance. The inflorescences are 4โ12 cm long, arranged as verticels (vertical stacks) formed from 3โ7 pairs of flower heads, and subtended by leafy bracts. Each verticel measures 0.5โ1.13 cm in diameter and holds 15โ30 pale yellow flowers, with corollas 4โ5 mm long. The plant produces capsules up to 2.5 mm long, containing numerous globose seeds that reach up to 0.4 mm in diameter. Buddleja utahensis is very rare in cultivation. It is difficult to grow in temperate regions, requiring very freely draining soil and infrequent watering. It is hardy to USDA zone 8.