Obedient Plant

Physostegia virginiana (Obedient Plant)
Photo: © Marie Iannotti

Overview and Description:

Obedient Plant (Physostegia virginiana) got its common name because you can bend the individual flowers in any direction you like - a nice feature for floral displays. Unfortunately, obedient plant is not so obedient in the garden, where it can spread quite aggressively, by rhizomes. Newer varieties, like ‘Miss Manners’, are being bred to remain in well-behaved clumps.

Obedient Plant has another common name, False Dragonhead, which I believe came about because of the flowers resemblance to snapdragons.

  • Foliage: The long, ovate, serrated leaves are pretty non-descript during the non-flowering part of the season. Some varieties turn red in the fall.
  • Flowers: Pastel shades of white, pink & lavender. The flowers form along spikes, in four neat vertical rows, and begin opening from the bottom up.
  • Form: Although obedient plant can spread throughout the garden, the individual plants tend to be clumpers. The flower stalks will bend and stay bent if moved or blown over. Large plants may require staking and mature plants will thin out in the center and can take on an open, floppy form, telling you it's time to divide them.

Botanical Name:

Physostegia virginiana

Common Name(s):

Obedient Plant, False Dragonhead

Hardiness Zones:

These are tough plants, reliably hardy in USDA Hardiness Zones: 3 - 10.

Mature Size:

Height - 24-48 inches (67-122 cm) x Width - 18-36 inches (46-91 cm)

Exposure:

Obedient plants are happiest in full sun, but they can handle partial shade, especially during dry summers.

Bloom Period:

The flowers begin to open in late summer, slowly blooming from the bottom of the flower stalk upward. They should remain in bloom well into fall.

Design Tips:

Obedient plant combines well with the blue flowers of the late summer garden, like Caryopteris, Russian sage, and Catmint. The spiky flowers are also a nice contract with asters, sedum, and coneflowers.

Because of its obedient habit, it’s a fun plant for children’s gardens. Flowers of the obedient plant make long lasting cut flowers.

Suggested Varieties:

  • Physostegia virginiana ' Miss Manners' - The name tells you this variety doesn’t spread. White flowers. 18-24 inches tall.

     

  • Physostegia virginiana 'Pink Bouquet' - Profuse bloomer. Soft pink flowers. Good choice for northern gardeners. 2-3 ft. tall.

     

  • Physostegia virginiana 'Summer Glow' - A tall grower with deeper lavender-pink flowers. 3-4 ft. tall.

     

  • Physostegia virginiana 'Variegata' - White edges on leaves make this variety interesting all season. Pink flowers. 18-24 inches tall.

     

  • Physostegia virginiana 'Vivid' - Forms short, dense clumps. Bright purple-pink flowers. 1-2 ft. tall.

Growing Tips:

Soil: Obedient plants are easily established and very drought tolerant, forgiving plants. Although they prefer a moist, slightly acidic soil (5.5 - 6.3 pH), they’ll grow just fine in average - poor soil and spreading will be less of a problem.

Propagating:Obedient  plant can be started from seed, about 2 months before planting out, or divide existing clumps in the spring. Cuttings taken from young, tender shoots also root well.

Feeding: Don’t fertilizer your obedient plants, unless they show signs of nutrient deficiencies.

Less fertilizer means less aggressive spreading.

Maintenance:

The biggest maintenance chore is keeping obedient plant from rampant spreading. Although the plants pull out easily enough, they seem to pop up everywhere. If you’re tempted to wait and let them flower, be sure to get out there before they go to seed.

Long season gardeners can get a second flush of blooms if you deadhead the first flowers. This will also cut down on the self-seeding.

Wait until spring to cut back old foliage. Leave it on the plants to act as a protective winter mulch.

Problems & Pests:

Obedient plant is not bothered by insects, except the occasional slug. Some seasons rust can be a problem. Obedient plant is deer resistant.