Obedient plant (Physostegia virginiana 'Crystal Peak White')
Physostegia virginiana 'Crystal Peak White' (Obedient plant) offers compact form, pure white summer blooms, and deer resistance for Zones 3-9.
Scroll down to discover growing tips, care requirements, companion plants, and more
Complete Plant Information
Overview
The Obedient plant, specifically the cultivar Physostegia virginiana ‘Crystal Peak White’, is highly valued for providing reliable, pure white flower spikes throughout the summer season. This compact variety maintains a tidy habit, unlike some taller relatives, making it excellent for modern garden designs where stature control is important. Physostegia virginiana ‘Crystal Peak White’ thrives in moist conditions, making it a superb choice for rain gardens or stream peripheries, while also offering deer resistance.
This rhizomatous perennial features upright, sturdy stems topped with tubular, snapdragon-like white flowers from early summer well into autumn. Its foliage remains attractive even outside the blooming period, contributing consistent texture to the border. Gardeners appreciate the Obedient plant for its ability to perform well under a variety of moisture regimes and its clean appearance.
Cultivars like Physostegia virginiana ‘Crystal Peak White’ are bred specifically to avoid the common issue of flopping stems, ensuring a strong vertical accent without the need for constant staking. Its common name comes from the unique characteristic where individual flowers remain temporarily posed in whatever direction they are pushed.
Fast Facts
- Plant Family: Lamiaceae
- Plant Type: Herbaceous perennial
- Hardiness Zones: USDA Zones 3-9
- Size at Maturity:
- Height: 1-1.5 ft
- Spread: 1.5-2 ft
- Bloom Time: June to September
- Bloom Description: White
- Sun Exposure: Full sun
- Water Needs: Medium
- Maintenance Level: Medium
How to Grow
Planting the Obedient plant is best done in spring or early fall, provided the soil is workable. Aim for a location receiving full sun, though it will tolerate some partial afternoon shade, especially in hotter climates. This perennial prefers average, moist, acidic, well-drained soils. Good drainage is essential to prevent root issues, even though the plant appreciates consistent moisture.
During the growing season, maintain medium moisture levels, especially as it prefers moist conditions. Stems may flop if the soil becomes too rich or if the plant is situated in deep shade or excessive summer heat. To ensure the compact habit of Physostegia virginiana ‘Crystal Peak White’ is maintained, avoid over-fertilizing. Taller, older varieties might require staking, but this cultivar is known for its short and sturdy stems.
For cleaner winter appearance, cut back the spent stems close to the ground in late fall or early spring before new growth emerges. The rhizomatous nature means the plant will spread, though the spread of ‘Crystal Peak White’ is reportedly less aggressive than the species. Monitor occasionally for signs of common pests like aphids or mites.
Landscape Uses
The primary appeal of Physostegia virginiana ‘Crystal Peak White’ lies in its reliable late-season color and structural integrity. It is highly valued for borders where its 1 to 1.5-foot height provides necessary mid-ground structure without obscuring shorter foreground plants. It blends seamlessly into cottage gardens or naturalized settings, particularly those featuring wild gardens or prairie plantings.
Its tolerance for wet soils makes it perfectly suited for placement on the peripheries of ponds, streams, or incorporated into rain gardens designed to manage runoff. The pure white flower spikes offer excellent contrast against blue or purple flowering companions. While beautiful in the ground, its compact nature also allows the Obedient plant to be successfully grown in containers, often treated as an annual feature if desired.
Standout Features
Flower Qualities
- Showy
Noteworthy Characteristics
Genus members are commonly called obedient plants because each individual flower will, upon being pushed in any one direction, temporarily remain in the new position as if it were hinged. ‘Crystal Peak White’ is specifically noted for its compact size, short and sturdy upright stems that resist flopping, and abundant blooms featuring pure white flowers that do not fade to brown. This cultivar of Physostegia virginiana offers reliable summer interest atop narrow, sharp-toothed foliage.
Tolerances
- Deer
- Clay Soil
Potential Problems
Rust is an occasional fungal issue to watch for, usually appearing as orange pustules on the leaves, which can be managed through good air circulation and avoiding overhead watering late in the day. Keep an eye out for minor infestations of aphids and spider mites, which can usually be controlled with insecticidal soap or a strong jet of water. While the species plant can be an aggressive spreader via rhizomes, this cultivar is reportedly much better behaved, requiring less vigorous containment.
Frequently Asked Questions
What hardiness zones is Obedient plant suitable for?
Physostegia virginiana ‘Crystal Peak White’ is hardy across USDA Zones 3 through 9.
How large does Obedient plant grow?
This cultivar typically reaches a height between 1 and 1.5 feet with a spread of 1.5 to 2 feet, maintaining a compact stature.
When does Obedient plant bloom?
The bloom time for the Obedient plant is generally from June to September, featuring abundant white flower spikes.
What sun exposure does Physostegia virginiana ‘Crystal Peak White’ need?
This plant performs best in full sun conditions but can tolerate some light afternoon shade, especially where summers are intense.
Conclusion
The Obedient plant, Physostegia virginiana ‘Crystal Peak White’, is an indispensable perennial that delivers robust vertical interest and clean white color reliably through the heat of summer. Its non-flopping stems and tolerance for moist soil make it a gardener’s asset in rain gardens and borders alike. Check your local climate to ensure your USDA zone falls between 3 and 9, and plan to plant this sturdy perennial this spring for season-long architectural beauty.
Companion Planting
Because the Obedient plant requires medium water and prefers moist soil, pair it with other moisture-loving perennials to create a cohesive visual and cultural block. Good companions include Astilbe, Ligularia, or certain varieties of Iris that naturally grow near water sources. In drier areas, ensure the soil remains consistently amended to satisfy the medium water needs of Physostegia virginiana ‘Crystal Peak White’. Clustering moisture-loving plants simplifies watering routines.
Design Ideas
The upright, spiky habit of Physostegia virginiana ‘Crystal Peak White’ makes it an excellent “thriller” element in container arrangements or a strong vertical punctuation mark in a mixed border. Use its pure white color to brighten up shady corners or to provide a visual resting spot among intensely colored companion flowers. In naturalized settings, allow it room to spread slightly, letting its rhizomes connect with native grasses for a meadow effect.
