Origin:
Dubautia plantaginea Gaud. ssp. plantaginea, commonly known as the plantain-leaved dubautia, is a species of flowering plant in the family Asteraceae, native to Hawaii in the United States. It is known to be found in the dry forests, shrublands, and rocky areas of the islands of Kaua?i, Ni?ihau, and O?ahu.
Common Names:
Besides Plantain-leaved Dubautia, Dubautia plantaginea Gaud. ssp. plantaginea is also commonly known as Na?ena?e (Hawaiian), Plantain Dubautia, and Silver Sword Plantain-leaved Dubautia.
Uses:
Dubautia plantaginea Gaud. ssp. plantaginea is mostly valued for its ornamental use in gardens or landscapes, planting in rock gardens and in pots. It is also revered in traditional Hawaiian medicinal practices for its possible uses in treating a variety of ailments. The leaves and stem of the plant are boiled and then used to make a compress for pain relief on sore muscles or bruises. Also, the poultice and juice extracted from the leaves of the plant are applied to cuts and wounds to induce faster healing.
General Appearance:
Dubautia plantaginea Gaud. ssp. plantaginea typically grows as a compact, non-woody shrub that reaches up to 6 feet in height. It has an erect stem, which is generally smooth with a grey-brown bark. The leaves of the plant are about 4-12 cm in length, and the blades are usually narrowly elliptical, arranged spirally and have no stem. Its leaves are distinguished by their prominent veins that resemble those of plantains, giving it its common name. The plant also produces yellow disc flowers that bloom sometime between January to May.
Growth Conditions of Dubautia plantaginea Gaud. ssp. plantaginea
Light: Dubautia plantaginea Gaud. ssp. plantaginea grows well in full sun to partial shade environments. However, it cannot tolerate excessive shade and grows very slowly in such conditions. Therefore, it is recommended to grow this plant in an area that receives at least six hours of sunlight per day.
Temperature: This plant species grows well in areas with a temperate climate. Its ideal temperature range is between 60 to 70 degrees Fahrenheit (15.5 to 21.1 degrees Celsius). Extreme temperatures, either hot or cold, can lead to the death of the plant.
Soil Requirements: Dubautia plantaginea Gaud. ssp. plantaginea prefers well-drained soils that are rich in organic matter. The soil should be slightly acidic with a pH range of 5.0 to 6.5. This plant species is adapted to grow in volcanic ash soils that have low nutrient content. Therefore, it is not advisable to amend the soil with excessive fertilizers. Instead, it is recommended to add a moderate amount of slow-release fertilizer during the growing period.
Cultivation
Dubautia plantaginea Gaud. ssp. plantaginea thrives in full sun to partial shade and prefers moist, rich, well-draining soil. It can be propagated from seeds or cuttings. Sow the seeds in the spring, and they will germinate in two to three weeks. Once the seedlings have established sturdy stems, transplant them to their permanent location. Alternatively, take cuttings in the late summer and root them in a well-draining potting mix.Watering Needs
Dubautia plantaginea Gaud. ssp. plantaginea requires regular watering, especially during the growing season. Water the plant deeply once or twice a week, depending on the weather conditions and soil moisture levels. Ensure that the soil is saturated to a depth of at least 6 inches. Reduce watering in the winter, but do not let the soil dry out completely.Fertilization
Dubautia plantaginea Gaud. ssp. plantaginea benefits from periodic fertilization to encourage healthy growth and abundant blooms. Apply a balanced, slow-release fertilizer in the early spring, and then once again in late summer. Alternatively, you can use a liquid fertilizer every two weeks during the growing season.Pruning
Dubautia plantaginea Gaud. ssp. plantaginea requires minimal pruning to keep it looking tidy and vigorous. Remove any dead, diseased, or damaged leaves and stems promptly. Pinch back the tips of the new growth in the spring to encourage bushier growth and more flowers. Avoid heavy pruning as this may harm the plant and reduce its flowering.Propagation of Dubautia plantaginea Gaud. ssp. plantaginea
The Dubautia plantaginea Gaud. ssp. plantaginea, commonly known as the smooth-leaved dubautia, can be propagated through various methods such as seed propagation, vegetative propagation, and division propagation.
Seed Propagation
Seed propagation is the most common way of propagating Dubautia plantaginea Gaud. ssp. plantaginea. The best time to collect the seeds is during the late summer and early fall when the seed capsules mature and turn brown. Once collected, the seeds must be stored in a cool and dry place to maintain viability. Before sowing, the seeds must be treated with a fungicide to prevent fungal infections. The seeds can be sowed using seeding trays filled with well-draining soil and kept moist. Germination can take up to three weeks, and the seedlings must be transplanted to bigger pots after the first set of true leaves develop.
Vegetative Propagation
Vegetative propagation can be done by taking stem cuttings from a healthy Dubautia plantaginea Gaud. ssp. plantaginea. The cuttings must be taken from new growth that is not yet woody and must be around 3 to 4 inches long. The leaves on the lower end of the cutting must be removed, and the stem must be dipped in rooting hormone powder. The stem cutting should be planted in well-draining soil and kept moist until new growth appears. After the new growth appears, the stem cutting can be transplanted to a bigger pot or directly to the garden.
Division Propagation
Division propagation is typically done during the plant's dormant season. To propagate using division, the plant must be dug out of the ground and separated into smaller sections carefully. The sections must contain healthy roots and some green foliage. The separated sections can then be planted into well-draining soil and kept moist until new growth appears.
Propagation of Dubautia plantaginea Gaud. ssp. plantaginea can be a rewarding process that allows gardeners to multiply their plants while preserving the species for generations to come.
Disease and Pest Management for Dubautia plantaginea Gaud. ssp. plantaginea
Dubautia plantaginea Gaud. ssp. plantaginea is a native Hawaiian plant that belongs to the Aster family and is commonly known as the Plantain-leaved Dubautia. It is a perennial plant that grows in dry to mesic forests, shrublands, and volcanic slopes. The following are common diseases and pests that can affect the plant, along with suggested management strategies.
Diseases
Ohia Wilt: This disease is caused by the fungus Ceratocystis fimbriata and affects the plant's vascular system, causing wilt and eventual death. The disease is spread by insects and contaminated equipment. Management strategies include using disease-free planting material, avoiding wounding the plant, maintaining good sanitation practices, and removing infected plants and debris.
Leaf Spot: This disease is caused by the fungus Phyllosticta dubautiae and shows up as circular brown spots on the leaves. To manage this disease, remove the affected plant parts, maintain proper plant spacing to allow for good air circulation, and avoid wetting the leaves while watering.
Pests
Thrips: These tiny insects feed on the plant's foliage and flowers, causing silvery discoloration and distortion. To manage this pest, remove and destroy infested plant parts, avoid over-fertilizing, and spray the plant with insecticidal soap or neem oil.
Spider Mites: These pests are common in dry and warm conditions and feed on the plant's sap, causing yellowing and mottling of the leaves. To manage spider mites, increase humidity around the plant, remove and destroy infested plant parts, and spray the plant with insecticidal soap or neem oil.
By following the outlined disease and pest management strategies, you can help protect and maintain the health of your Dubautia plantaginea Gaud. ssp. plantaginea for an extended period.
