PL. —Physostegia virginianaBotanical illustration — drop image
Physostegia virginiana

Obedient Plant

SummerFall
2b9aHardiness zone
Peak bloom windowZone 6b · frost-offset weeks
Winter
Not in bloom
Spring
Not in bloom
Summer
Peak bloom
Fall
Not in bloom
Peak bloom
In bloom
Background

Physostegia virginiana is a native North American perennial in the mint family that grows naturally in moist meadows, stream banks, and open woodlands from eastern Canada to northern Mexico. Its tubular pink or white flowers appear from late summer into fall, filling a gap when many other perennials have finished. The common name comes from the plant's unusual pedicel structure: individual flowers pushed sideways on the square stem will hold that position rather than spring back.

The plant spreads aggressively by rhizomes and can overrun smaller neighbors within a few seasons. Compact cultivars such as 'Miss Manners' and 'Pink Manners' have a much less invasive habit and suit mixed borders better than the straight species. In rain gardens or naturalistic plantings where spread is acceptable, it colonizes quickly and suppresses weeds. Full sun and consistent moisture produce the sturdiest stems; in rich soils, early-season pinching or staking may be needed to prevent flopping. Dividing clumps every two to three years maintains vigor and limits territorial creep. Mulching around the root zone helps retain the consistent moisture it prefers and moderates soil temperature through summer.

Young shoots were used as a cooked potherb by several Native American peoples. Bumblebees and hummingbirds are the primary pollinators, and the plant's dense colonial growth provides nesting cover and seed food for ground-foraging birds through fall and winter.

Care guide
SunFull sun to part shade — 4+ hours daily
Water1 inch per week; moist soil preferred
SoilMoist to average; pH 5.5–7.0
Spacing18–24 inches
Height24–48 inches
Zone2b – 9a
Native RegionAL, AR, CT, DE, DC, FL, GA, IL, IN, IA, KS, KY, LA, ME, MD, MA, MI, MN, MS, MO, NE, NH, NJ, NY, NC, OH, OK, PA, RI, SC, SD, TN, TX, VT, VA, WV, WI
Frost hardy
Seasonal tasks
spring
cutDivide established clumps in early spring before new growth reaches 6 inches to control spread and reinvigorate the planting.
sowSet out transplants or rooted divisions in prepared, moist soil around the last frost date.
summer
watchMonitor bed edges weekly for escaping rhizomes; sever and remove runners before they root into adjacent plantings.
watchInspect foliage for powdery mildew, particularly in humid conditions with poor air circulation around dense clumps.
watchCheck new stem tips for aphid colonies; dislodge with a firm stream of water or apply insecticidal soap if populations are heavy.
cutPinch stem tips back by one-third in early summer to encourage branching and reduce flopping in fertile soils.
fall
cutCut all stems to ground level after the first hard frost kills back the foliage.
sowSurface-sow seed outdoors in fall; natural cold stratification over winter improves germination the following spring.
Common problems

Powdery mildew

Symptoms

White or grey powdery coating on leaves — usually starting on older growth in humid conditions or when nights cool.

Treatment

Improve air circulation by thinning plants. Apply neem oil or potassium bicarbonate spray at first sign. Avoid overhead watering.

Crown Rot

Symptoms

Lower leaves yellow and wilt; the base of the rosette turns brown and soft, sometimes with white fungal threads at the soil line. Plants collapse in wet conditions.

Treatment

Remove and destroy affected plants. Improve drainage and avoid overhead watering. Do not mulch directly against the crown. Space plants for airflow and avoid replanting in the same wet spot.

Pests

Aphids

Aphididae
Symptoms

Clusters of small soft insects on new growth and flower buds.

Treatment

Knock off with a strong jet of water. Ladybirds and lacewings are natural predators. Insecticidal soap as last resort.

Slug and Snail Damage

Deroceras reticulatum
Symptoms

Large irregular holes chewed in leaves, with slime trails on foliage and soil.

Treatment

Hand-pick at night, set beer traps, or apply iron phosphate bait. Remove debris and mulch where they hide.