Caper (Capparis sandwichiana)
Discover Capparis sandwichiana, the Hawaiian Caper genus native to Hawaii. This evergreen shrub thrives in coastal, dry, full-sun conditions.
Complete Plant Information
Overview
Capparis sandwichiana, commonly known as the Caper or maiapilo, is a fascinating, narrowly endemic species critical to Hawaiian ecosystems. This broadleaf evergreen offers a unique, sprawling structure, making it valuable for softening harsh landscapes, particularly those near the coast. Gardeners in appropriate zones value this Caper for its resilience and distinctive presence.
As a shrub native only to the Hawaiian islands, Capparis sandwichiana adapts well to challenging environments. It prefers open, windswept, rocky, or sandy terrains, exhibiting excellent drought tolerance once established. While it requires full sun, its adaptability to coastal exposure, including salt spray, sets it apart.
Aesthetically appealing, this Caper produces fragrant, night-blooming flowers, often white with long stamens, which attract specialized local moths. Its low-growing, spreading habit, reaching up to 15 feet wide, makes it an excellent textural element in xeriscapes or rock gardens where Mediterranean or desert planting styles are desired.
Fast Facts
- Plant Family: Capparaceae
- Plant Type: Broadleaf evergreen
- Native Range: Hawaii
- Hardiness Zones: USDA Zones 10-12
- Size at Maturity:
- Height: 3-15 ft
- Spread: 6-15 ft
- Bloom Time: Seasonal bloomer
- Bloom Description: White, Pink, Yellow
- Sun Exposure: Full sun
- Water Needs: Dry
- Maintenance Level: Medium
How to Grow
Planting Capparis sandwichiana should ideally occur during warmer periods to encourage root establishment, ensuring it is placed in the driest available spot. This Caper demands soils that are loose, well-draining, and preferably rocky or sandy, mimicking its native coastal habitat. Avoid locations where water pools, as drainage is paramount for the survival of this species.
Care for this plant centers almost entirely on minimizing excess moisture. Watering should be infrequent; only water during prolonged, severe dry spells if there is no natural precipitation. Fertilization is generally unnecessary, as rich inputs can promote softer growth susceptible to damage. Pruning may be required only to manage sprawling branches or remove any deadwood, particularly after periods of heavy rain.
A key consideration for establishing this Hawaiian Caper is patience. Capparis sandwichiana may establish slowly, especially when first placed in a new environment. Once established, however, it exhibits marked tolerance to drought and salt spray, making it an ultra-low-maintenance specimen for dry, coastal gardening projects within its narrow hardiness range.
Landscape Uses
The sprawling nature of Capparis sandwichiana makes it exceptionally suitable for serving as a dense ground cover in challenging locations. It excels when utilized in coral or lava rock gardens where standard shrubs may struggle with lean soils. Consider planting several specimens close together to form a low hedge or textural border along pathways or dry embankments.
Due to its specific cultural needs—dry, well-draining soil and full sun—this Caper pairs well with other xeriscape specialists native to warm, coastal regions, such as certain agaves or hardy succulents that share a preference for lean, rocky substrates. Avoid planting near moisture-loving perennials.
Its use as a ground cover is highly recommended for minimizing erosion on slopes in appropriate climates. When established, the maturity of this Caper species allows it to provide textural contrast against hardscape materials, enhancing the natural, rugged beauty of seaside landscapes.
Standout Features
Flower Qualities
- Showy
- Fragrant
Noteworthy Characteristics
Capparis sandwichiana, commonly called maiapilo or Hawaiian caper, is a narrowly endemic caper species native only to the eight main islands of Hawaii and several outlying islets and atolls. It is found growing on open, windswept, rocky, coastal areas and occasionally farther inland. A sprawling to mounded evergreen shrub, mature prostrate specimens can have branches up to 15’ long spread along the ground, while more upright specimens can reach 6’ tall. The fragrant, night-blooming flowers are white with numerous, long, showy stamens.
Tolerances
- Drought
- Dry Soil
- Shallow-Rocky Soil
Potential Problems
The primary threats to Capparis sandwichiana stem from environmental mismanagement, especially excessive moisture. Overwatering or planting in poorly drained soil is typically fatal to this highly drought-tolerant native plant. Additionally, the foliage can be temporarily damaged by the caterpillars of the introduced cabbage butterfly, which may leave holes along the leaf margins. Stem dieback, though less common, can occur, especially following periods of consistently rainy weather.
Frequently Asked Questions
What hardiness zones is Caper suitable for?
This Caper species is hardy in USDA Zones 10 through 12, thriving in environments that rarely experience frost.
How large does Capparis sandwichiana grow?
Mature specimens of Capparis sandwichiana can range significantly in habit, reaching heights between 3 and 15 feet tall, with a spread that can cover an area between 6 and 15 feet wide.
What sun exposure does Caper need?
This plant requires full sun exposure to perform optimally and maintain its dense, sprawling structure.
When does Caper bloom?
This plant is noted as a seasonal bloomer, producing flowers described as White, Pink, and Yellow.
Conclusion
Incorporating Capparis sandwichiana into your garden design offers solutions for harsh, dry, or coastal planting areas where other shrubs fail. This resilient Caper provides unique texture and attracts specialized local wildlife, reinforcing native ecology. Always confirm that your site provides the necessary full sun and superb drainage before planting your Capparis sandwichiana.
Wildlife Benefits
The unique pollination syndrome of this native Caper species highlights its importance in the Hawaiian ecosystem. The fragrant, night-blooming flowers serve as a critical nectar source specifically for Blackburn’s sphinx moth (Manduca blackburni). For larval stages, this plant is a designated host providing sustenance for the endemic diamondback moth (Plutella capparidis).
Planting this Caper isn’t just about horticulture; it is about supporting documented faunal relationships. Its oblong fruits, which mature to yellow, are also noted to be attractive to various native birds, facilitating localized seed dispersal.
Common Mistakes
The most significant error when cultivating Capparis sandwichiana is providing too much water or insufficient drainage. As a species evolved for rocky coasts, attempts to treat it like a standard garden shrub by watering regularly will likely lead to root rot and stem dieback. Furthermore, attempting to grow this plant extensively inland, far from coastal influence or in rich, water-retentive garden loam, will compromise its vigor.
Avoid planting it in partially shaded areas, as insufficient light will result in leggy, sparse growth rather than the desired mounded or prostrate coverage. Remember, this Caper thrives under conditions that would stress many other ornamental species.
