Fall Obedient Plant, Physostegia virginiana: Shade to part-sun perennial
Description: Fall Obedient Plant, Physostegia virginiana, also called False Dragonhead, is in the mint family. It grows 2-5 feet tall and 1-2 feet wide, with square stems and opposite, toothed leaves that grow up to 5” long and 1.5” wide and are smaller at the top of the stems. The plant’s common name comes from the observation that individual flowers in the flower spike will stay in place if they are manipulated into a new position.
Flowers and Seeds: Fall Obedient Plant blooms in late summer through mid-fall in North Texas. The 2/3-1” white to light- to deep-pink to lavender flowers are found on 4-6” spikes that start blooming at the bottom of the spike to the top. Several cultivars varying in flower color are available. Dead-heading the flowers encourages more blooms. The flowers are followed by seed capsules with small black self-sowing seeds.
Planting sites: Fall Obedient Plant thrives in part shade to sun and a range of soil types, including clay and poor soil. In the wild, it can be found in marshy sites. During drought, it may go dormant.
Watering Instructions: During dry spells, Fall Obedient Plant will appreciate supplemental water, especially if planted in full sun. Unlike many other native Texas plants, it tolerates poor drainage, making it valuable for rain gardens.
Comments: Fall Obedient Plant is great in border, meadow, butterfly, cutting and native plant gardens, as well as pocket prairies or close to a water feature. Taller plants may need to be staked if they become floppy. It is easy to propagate by seed or by digging up the roots. It spreads easily by rhizomes and can be aggressive, a characteristic common to mint family members. However, its shallow roots mean that it can be easily weeded out where it is not wanted. Fall Obedient Plant attracts butterflies, hummingbirds and native bees and is deer resistant. Consider planting Fall Obedient Plant instead of invasive, non-native yellow-flag iris (Iris pseudacorus) and Umbrella plant (Cyperus alternifolius). Although Fall Obedient Plant is related to both Spring Obedient Plants (P. intermedia and P. pulchella), it blooms at a different time. Because all three have otherwise similar soil and water needs, consider growing them as companion plants. Other companion plants include the perennial Cardinal Flower (Lobelia cardinalis) and the annual Texas Bluebells (Eustoma exaltata var. grandiflora). Big Red Sage (Salvia penstemonoides) and Texas Betony (Stachys coccinea) are also suitable companions for Fall Obedient Plant in areas with good drainage.
Written by Dr. Becca Dickstein