Isodon effusus, commonly known as Long-Tubed Trumpet Spurflower, is a deciduous perennial herb native to the understory of moist deciduous forests in Japan. This plant typically grows to a height of 2-4 feet (0.6-1.2 meters) and a width of 2-3 feet (0.6-0.9 meters). It features an upright, clumping form with lance-shaped leaves and produces tubular, purple flowers that are arranged in whorls along the stem, blooming in late summer to fall. The flowers are quite showy and attract pollinators such as bees and butterflies.

Long-Tubed Trumpet Spurflower is valued for its late-season blooms and its ability to thrive in shaded garden areas where other flowering plants may not perform as well. It is used in border plantings, woodland gardens, and as an accent plant in mixed beds. This species prefers consistently moist, well-drained soils rich in organic matter and can tolerate a range of light conditions from part shade to full sun. While generally low-maintenance, it may require staking in very rich soils or overly shaded conditions to prevent stem flopping. It is not known for serious pest or disease problems, but good air circulation can help prevent fungal issues.CC BY-SA 4.0