Oregon Grape Mahonia × wagneri 'Pinnacle'
ABOUT
Mahonia × wagneri 'Pinnacle', commonly known as the Oregon grape, is a striking evergreen shrub noted for its attractive year-round features. It has a dense, upright growth habit with multiple stems emanating from the base, which gives it a robust and bushy appearance. The foliage of the Oregon grape is one of its most defining characteristics; it sports compound leaves that are reminiscent of holly, with a glossy, deep green color and sharp-toothed leaflets that spread out in a feather-like arrangement on each stem. These leaves can sometimes take on a reddish tinge during cooler months, adding to the plant's seasonal appeal. Springtime brings a splash of color with the appearance of bright yellow flowers, which are small but abundant and form in tight clusters at the ends of the stems. These tiny flowers have a distinctive, cupped shape that makes them a cheerful sight in the garden. By late summer and into fall, the flowers give way to bluish-black berries, which are small and round, often with a frosty bloom on their surface. These fruits are decorative and can attract birds and wildlife to the garden. The Oregon grape's leathery texture, along with its spiky leaf margins, provides a unique tactile experience, and the plant is often used in landscapes for its striking form and foliage. Together, these features make the Oregon grape a visually appealing plant that enhances both formal and informal garden settings throughout the seasons.
About this plant
NamesFamily
Berberidaceae
Synonyms
Oregon Grape, Pinnacle Mahonia
Common names
Mahonia × wagneri 'Pinnacle'
ToxicityTo humans
Oregon grape is not commonly regarded as a highly toxic plant to humans, but it can cause unpleasant symptoms if ingested in significant quantities. Parts of the plant contain alkaloids, including berberine, which can lead to symptoms such as vomiting, diarrhea, lethargy, and confusion. It is especially important to keep children away from the berries, as they might be tempted to eat them due to their appearance and their relatively higher susceptibility to toxins. In general, it's advised not to consume any part of the Oregon grape without proper knowledge or preparation.
To pets
Oregon grape is also considered to have a low level of toxicity to pets such as dogs and cats, but like in humans, the consumption of significant amounts of the plant, particularly the berries, can cause gastrointestinal upset. Symptoms in pets might include vomiting, diarrhea, and general weakness. As pets can be more sensitive to certain compounds, it is best to prevent them from ingesting any part of the Oregon grape to avoid any potential health issues. If a pet does consume some of the plant and exhibits symptoms, it is advisable to contact a veterinarian.
CharacteristicsLife cycle
Perennials
Foliage type
Evergreen
Color of leaves
Green
Flower color
Yellow
Height
15 feet (4.57 meters)
Spread
5 feet (1.52 meters)
Plant type
Shrub
Hardiness zones
5
Native area
Cultivar
Benefits
General Benefits- Attractive foliage: Mahonia × wagneri 'Pinnacle' has evergreen leaves that provide year-round interest in the garden.
- Drought resistance: Once established, this plant is quite drought-tolerant, requiring minimal water and making it suitable for xeriscaping.
- Erosion control: The robust root system helps stabilize soil and prevent erosion on slopes.
- Low maintenance: It requires little maintenance once established, with only occasional pruning to shape or remove damaged fronds.
- Wildlife support: The yellow flowers attract pollinators such as bees while the blue-black berries provide food for birds.
- Architectural interest: With its upright growth habit, Mahonia × wagneri 'Pinnacle' can provide vertical interest in landscape design.
- Shade tolerance: This plant can grow well in partial shade, making it a versatile choice for different garden situations.
Medical PropertiesThis plant is not used for medical purposes.
Air-purifying QualitiesThis plant is not specifically known for air purifying qualities.
Other Uses- Mahonia 'Pinnacle' can be used as a natural dye source; its berries produce a light yellow to greenish-yellow color that can be used for dyeing fabrics and yarns.
- The stiff and spiny foliage of 'Pinnacle' can serve as a barrier plant in gardens, deterring animals and unauthorized entry into private areas.
- Its dense growth habit provides a natural shelter for birds and small wildlife, serving as a safe haven from predators and harsh weather.
- With its attractive foliage and berries, 'Pinnacle' is a suitable plant for creating intricate and colorful botanical prints on paper or textiles.
- The tall, erect form of 'Pinnacle' makes it suitable for use in vertical gardens or living walls, where it adds height and structure.
- The wood of 'Pinnacle' can be used in small scale carpentry or as decorative elements in woodwork projects, taking advantage of its hardness and texture.
- Dried stems and berries of 'Pinnacle' can be incorporated into floral arrangements and wreaths, offering a unique texture and color contrast.
- Photographers can use 'Pinnacle' as a subject or backdrop in garden photography, capturing the seasonal changes and its striking appearance.
- It can be employed as a companion plant in mixed borders, its bold foliage contrasting nicely against softer, finer-textured plants.
- Mahonia 'Pinnacle' can also serve as an educational tool in horticultural programs, illustrating plant breeding, adaptation, and hybrid vigor.
Interesting Facts
Feng ShuiThe Oregon grape is not used in Feng Shui practice.
Zodiac Sign CompitabilityThe Oregon grape is not used in astrology practice.
Plant Symbolism- Resilience: Mahonia, also known as Oregon Grape, exemplifies resilience through its hardy nature and ability to thrive in various conditions, often symbolizing strength and adaptability.
- Protection: The spiny leaves of Oregon Grape are reminiscent of holly, often associated with protection and the ability to ward off negativity or danger.
- Healing: With its history of medicinal use, particularly by Native American tribes, Oregon Grape symbolizes healing and the nurturing of health and well-being.
WaterOregon grape 'Pinnacle' should be watered deeply but infrequently, allowing the soil to dry out slightly between waterings. During the growing season, watering once a week with 1-2 gallons per plant is typically sufficient. However, in extremely hot or dry weather, check the soil more frequently and water as needed to prevent drought stress. In the fall and winter, reduce the frequency of watering to match the plant's decreased water needs. Ensure that the plant has well-draining soil to avoid waterlogging and root rot.
LightOregon grape 'Pinnacle' thrives best in partial shade to full sun. Its ideal spot is one that receives morning sunlight and afternoon shade or dappled sunlight throughout the day. Too much direct, hot sun can scorch the leaves, while too much shade can lead to poor growth and fewer flowers.
TemperatureOregon grape 'Pinnacle' is hardy and can tolerate a broad range of temperatures, from as low as 0°F to around 90°F. Optimum growth occurs within a temperate range of 50°F to 80°F. It is important to avoid extreme temperature fluctuations and provide protection from harsh winter winds that can cause damage to the foliage.
PruningOregon grape 'Pinnacle' is pruned to maintain its shape, remove dead or damaged wood, and to encourage new growth. Pruning should be done in late winter or early spring before new growth begins. Typically, this plant requires light pruning to shape it and to thin out crowded areas, which can be performed every year or every other year, depending on its growth.
CleaningAs needed
SoilOregon grape 'Pinnacle' thrives in well-draining, fertile soil with a pH range of slightly acidic to neutral (6.0-7.5). A soil mix of loam, compost, and coarse sand or perlite works well, ensuring good aeration and drainage.
RepottingOregon grape 'Pinnacle' is a slow-growing plant and does not need frequent repotting. Repot every 2-3 years, or when roots outgrow the current container, typically in early spring.
Humidity & MistingOregon grape 'Pinnacle' prefers moderate humidity levels but is adaptable to lower indoor humidity. It tolerates average room humidity, making it relatively low maintenance in this regard.
Suitable locationsIndoor
Place in bright, indirect light, and keep soil moist.
Outdoor
Plant in part shade, well-drained soil, mulch annually.
Hardiness zone
5-9 USDA
Life cycleMahonia × wagneri 'Pinnacle', commonly known as Oregon grape, follows a typical perennial shrub life cycle. It begins as a seed which, upon germination in favorable conditions of moist, well-drained soil and partial to full shade, sprouts into a seedling. The seedling then grows into a juvenile plant, developing a strong root system and initial foliage. As it reaches maturity, it forms leathery evergreen compound leaves, and in the spring, it produces yellow flowers arranged in dense, upright racemes. Following pollination, often by bees, these flowers give way to dark blue, edible berries with a waxy coating. Throughout its life, which can last for many years, the Oregon grape undergoes seasonal growth and dormancy, with pruning and occasional division helping to maintain its vigor and shape.
PropogationPropogation time
Spring to Summer
The Oregon grape 'Pinnacle' can be propagated through semi-hardwood cuttings, which is the most popular method. This involves taking cuttings of the plants' stems in late summer when the new growth has started to harden. Typically, a cutting of 4-6 inches (10-15 cm) long with several leaf nodes is ideal. The bottom leaves are removed and the cut end of the stem is dipped into rooting hormone to encourage root development. The prepared cutting is then planted in a well-draining soil mix, keeping the soil moist but not waterlogged. The cutting should be put in a location with indirect light and covered with a plastic bag or placed in a propagator to maintain humidity. Roots usually develop within a few weeks to months, depending on the conditions.
