Calystegia soldanella
A prostrate coastal bindweed with fleshy, nearly circular leaves and showy pink to white funnel-shaped flowers. Binds sands and stabilizes foredunes; highly salt- and wind-tolerant among our coastal plants.
| Scientific Name | Calystegia soldanella |
|---|---|
| Height | 0.3-0.6 m spread |
| Water Needs | Moderate, drought tolerant when established |
| Light | Full sun |
| Spread | Extensive; can spread 2-5 m or more |
| Frost Tolerance | Hardy once established |
| Salt Tolerance | High; excellent for coastal conditions |
| Growth Rate | Fast growing |
| Lifespan | Long-lived perennial |
Calystegia soldanella, also known as Shore Bindweed, is highly adapted to temperate coastal climates globally. It thrives in harsh conditions, demonstrating excellent tolerance to salty wind and salt spray. This species requires bright, direct sunlight for at least six hours daily and cannot tolerate shaded environments. While it prefers moist, well-drained soil, it can endure brief dry periods. It is hardy to moderate frosts, typically tolerating temperatures down to -10°C (14°F). Its natural distribution spans coastal regions across both the Northern and Southern Hemispheres, indicating its adaptability to a wide range of temperate coastal zones.
| City | Climate Suitability |
|---|---|
| Whangārei | Ideal |
| Auckland | Ideal |
| Hamilton | Ideal |
| Tauranga | Ideal |
| Rotorua | Ideal |
| Gisborne | Ideal |
| New Plymouth | Ideal |
| Napier | Ideal |
| Whanganui | Ideal |
| Palmerston North | Ideal |
| Wellington | Ideal |
| Nelson | Ideal |
| Christchurch | Ideal |
| Dunedin | Ideal |
| Invercargill | Ideal |
Calystegia soldanella thrives in full sun, requiring at least 6 hours of direct sunlight daily. It cannot grow in shaded areas.
This plant prefers sandy, well-draining soils. It can tolerate nutrient-poor conditions and grows well in beach sand, shell banks, fine gravel, or pumice. It adapts to mildly acidic, neutral, or mildly alkaline soils.
Accustomed to coastal conditions, Calystegia soldanella prefers consistent moisture but can tolerate brief periods of dryness. Water when the soil is almost completely dry, typically weekly during dry spells.
Calystegia soldanella plays a crucial role in coastal ecosystems by stabilizing sand dunes and preventing erosion, thus preserving habitats for various wildlife. It also serves as a food source for birds and insects.
With its attractive trumpet-shaped flowers (ranging from pink to white or lavender) and distinctive kidney-shaped, fleshy leaves, Shore Bindweed has ornamental value and can be an attractive addition to coastal gardens.
Historically, the young shoots of Calystegia soldanella have been consumed as a vegetable, and its flexible stems used as string. Medicinally, it has been used as an antiscorbutic, diuretic, febrifuge, irritant, purgative, and vermifuge in traditional practices.
In early spring, prune any dead or damaged stems to encourage new growth and flowering. This is also an ideal time for propagation by division of rhizomes while the plant is dormant. If transplanting, do so in late spring to early summer after the last frost.
Summer is the peak flowering season for Shore Bindweed, with trumpet-shaped flowers appearing from mid-spring to early fall. Ensure consistent moisture, especially during dry spells, but allow the soil to dry out between waterings. Minimal pruning can be done after flowering to enhance vigor.
As temperatures cool, the plant may begin to enter dormancy. Reduce watering frequency as growth slows. Avoid heavy pruning in autumn to protect the plant during colder months.
Shore Bindweed typically enters a dormant period during winter. Minimal care is required. Protect young plants from severe frost if necessary, though mature plants are generally hardy to moderate cold.
Calystegia soldanella, or Shore Bindweed, generally does not require extensive pruning due to its prostrate growth habit. However, light maintenance pruning can be beneficial for its health, appearance, and to manage its spread.
Always use sharp and sterile pruning shears to make clean, precise cuts, minimizing stress to the plant and reducing the risk of disease.
The ideal time to plant Calystegia soldanella is in late spring to early summer, after the last risk of frost has passed. This allows the plant to establish robust root growth in warmer conditions.
Choose a site that mimics its natural coastal habitat:
Water regularly during the first few weeks after planting to help establish the root system. Once established, Calystegia soldanella is quite drought-tolerant but will benefit from occasional deep watering during prolonged dry periods.
Seed propagation provides an effective and authentic method for growing Shore Bindweed that maintains the genetic diversity essential for this coastal native species adapted to challenging sandy beach environments. This robust perennial vine produces distinctive round capsules containing dark brown seeds that are naturally dispersed by both water and wind, making seed collection and propagation a natural choice for restoration projects and coastal gardens. Seeds develop throughout most of the year following the characteristic pink and white trumpet-shaped flowers that bloom extensively from September to March, providing multiple opportunities for collection during the extended fruiting season. For optimal germination success, collect mature seeds from fully developed capsules that have turned brown and begun to split naturally, indicating peak seed viability and readiness for dispersal. Fresh seed provides the best germination rates and should be collected on calm, dry days when capsules can be easily harvested without loss. To improve germination rates for this hard-seeded coastal species, pre-treat seeds by soaking them in warm water for 2 hours or carefully nick the seed coat with a sharp blade to allow moisture penetration through the tough outer coating. Alternatively, brief treatment with a 5% bleach solution for 3 minutes can help break dormancy while providing surface sterilization. Sow pre-treated seeds in well-draining sandy potting mix that replicates the natural beach sand conditions where this species thrives, using containers that provide excellent drainage to prevent waterlogging. For natural stratification that mimics coastal winter conditions, expose seed trays to moist, cool conditions throughout winter, maintaining temperatures around 5-10°C to satisfy dormancy requirements. Alternatively, sow seeds in cold frames during spring, barely covering them with sand as they require some light for optimal germination. Maintain consistent moisture without waterlogging throughout the germination period, which typically occurs within 1-3 months at temperatures around 15°C. Young seedlings develop slowly initially but form robust root systems adapted to sandy coastal conditions, requiring patience and careful management during their early growth phases before transplanting to permanent coastal garden locations.
Cutting propagation offers a reliable vegetative method for multiplying Shore Bindweed, particularly valuable for maintaining the exact characteristics of superior coastal garden forms and for rapid establishment of ground cover in challenging seaside conditions. This technique takes advantage of the plant's natural vigor and ability to develop roots readily from stem material during the active growing season. The optimal timing for taking cuttings is during summer when the plant is actively growing and stems have adequate stored energy for root development, typically from November through February in New Zealand coastal conditions. Select healthy, vigorous shoots from the current season's growth that are approximately 10-15cm in length, choosing material from non-flowering stems to direct energy toward root development rather than reproduction. Take cuttings early in the morning when plant tissues are fully hydrated, using clean, sharp secateurs to make clean cuts just below a node where root development will be most successful. Remove lower leaves from each cutting, leaving only 2-3 pairs of upper leaves to reduce moisture loss while maintaining sufficient photosynthetic capacity during the rooting phase. Prepare a well-draining cutting medium using coarse sand mixed with perlite or pumice to replicate the free-draining conditions essential for preventing cutting rot in this coastal species. Insert cuttings into the sandy medium, ensuring good contact between the cutting base and rooting medium while maintaining adequate spacing for air circulation. Place cutting containers in a protected environment with bright, indirect light and moderate humidity, avoiding the extreme conditions that could stress these coastal-adapted cuttings. Maintain consistent moisture without waterlogging, as Shore Bindweed cuttings are susceptible to rot in overly wet conditions. Root development typically occurs within 3-6 weeks under suitable conditions, with new growth appearing as an indicator of successful root establishment. Once well-rooted, gradually acclimatize cuttings to outdoor conditions before transplanting to their permanent coastal garden locations. This method provides faster establishment than seed propagation and is particularly effective for creating uniform plantings in coastal restoration projects.
Rhizome division represents the most straightforward propagation method for established Shore Bindweed, taking advantage of the plant's natural spreading habit through underground rhizomes that create expanding colonies across coastal sand dunes and shoreline areas. This method is particularly valuable for managing established plantings, creating new coastal garden areas, and for restoration projects where rapid ground cover establishment is essential for erosion control. The optimal timing for rhizome division is during early spring just as new growth begins to emerge, providing divided sections with the full growing season to establish extensive root systems before facing winter coastal storms. Shore Bindweed naturally spreads through creeping rhizomes that extend horizontally through sandy soil, producing new shoots at regular intervals and creating ideal opportunities for division into independent plants. Begin by carefully excavating around established clumps to expose the rhizome system, working gently to preserve the extensive but often shallow root network that spreads through coastal sand. Use clean, sharp tools to divide rhizomes into sections, ensuring each division includes both healthy rhizome material and several growing points or emerging shoots for successful establishment. Divisions can be quite small as this vigorous coastal species establishes readily, though larger sections provide more immediate impact and faster coverage. Each division should include sufficient rhizome length to support the plant during establishment, typically 10-15cm sections with multiple nodes and associated root development. Replant divisions immediately in well-draining sandy soil that matches their natural coastal habitat, positioning them at the same depth they were previously growing. Choose locations that receive full sun to partial shade with excellent drainage, as waterlogged conditions can quickly damage these sand-adapted plants. Water thoroughly after planting but avoid overwatering, as Shore Bindweed is adapted to coastal conditions where moisture comes primarily from rainfall and sea spray. Maintain consistent moisture during the establishment period while divisions develop new root systems and adapt to their new locations, typically 4-6 weeks during favorable growing conditions.
Calystegia soldanella, commonly known as Shore Bindweed, is generally a robust and resilient plant with few serious pest or disease issues, especially when grown in its preferred coastal conditions.
Shore Bindweed is generally considered disease-free. Most issues related to plant health are often a result of unsuitable growing conditions rather than specific pathogens.
Maintaining optimal growing conditions, including full sun and well-drained soil, is the best defense against pests and diseases for Calystegia soldanella. Healthy plants are more resistant to potential threats.
Calystegia soldanella is a true coastal specialist with unique adaptations. Its fleshy, waxy, and somewhat succulent leaves are perfectly designed to reduce water loss and reflect sunlight, allowing it to thrive in harsh coastal environments. This makes it an excellent choice for stabilizing sandy soils and preventing erosion on coastal dunes, contributing significantly to the ecological health of these fragile ecosystems. Despite its relation to more aggressive bindweed species, Calystegia soldanella is generally not considered invasive in garden settings, making it a well-behaved and beneficial addition to coastal or xeriscape gardens.
Explore other coastal plants that share similar characteristics or habitats with Shore Bindweed, offering complementary planting opportunities.
Understanding the natural habitat of Calystegia soldanella provides insights for successful cultivation and conservation.
The ecological interactions of Shore Bindweed demonstrate its specialized adaptations to harsh coastal environments.
While Calystegia soldanella is widely distributed globally, localized populations face pressures from coastal development and climate change.
Advanced cultivation techniques for optimal Shore Bindweed performance in various garden settings.
Shore Bindweed offers unique design opportunities for coastal and xerophytic landscape applications.
A prostrate coastal bindweed with fleshy, nearly circular leaves and showy pink to white funnel-shaped flowers. Binds sands and stabilizes foredunes; highly salt- and wind-tolerant among our coastal plants.
For successful establishment of Calystegia soldanella, proper site preparation and planting technique are essential for this specialized coastal plant.
Shore Bindweed (Calystegia soldanella) holds cultural importance in Aotearoa New Zealand through its roles in traditional knowledge and native ecosystems.
