Overview
Dubautia scabra (DC.) Keck var. leiophylla (Gray) Keck is a flowering plant species belonging to the Asteraceae family. This plant is native to Hawaii, specifically found on the islands of Maui and Kahoolawe. It is commonly known as the Kahoolawe Dubautia or the Maui Dubautia.Description
Dubautia scabra var. leiophylla is a shrub that can grow up to three meters tall. The plant's stem is woody and covered with rough bark. The leaves are elongated, narrow, and have a leathery texture. They are shiny green on the upper surface and pale and fuzzy underneath. The plant produces small, white or pale yellow flowers that grow in clusters at the ends of the branches.Uses
In traditional Hawaiian culture, Dubautia scabra var. leiophylla was used medicinally to treat stomach ailments and colds. It was also employed as an infusion for bathing and soaking in to alleviate skin conditions. The plant's leaves were also used to make leis for special occasions. Currently, Dubautia scabra var. leiophylla is used mainly for its ornamental qualities. It is grown in gardens and parks for its attractive foliage and delicate flowers. The plant is adaptable to various soils and can tolerate salt spray and wind exposure, making it ideal for coastal landscapes.Conservation Status
Dubautia scabra var. leiophylla is classified as an endangered species by the International Union for Conservation of Nature (IUCN). The plant's natural habitat is threatened by habitat loss due to human activity, especially the clearing of land for agriculture and urbanization. Invasive plant species such as fountain grass (Pennisetum setaceum) and lantana (Lantana camara) also pose a significant threat to the plant's survival. Ongoing conservation efforts aim to restore and protect the plant's natural habitat and ensure its long-term survival.Light Requirements
Dubautia scabra var. leiophylla prefers full sun to partial shade. It can tolerate some shade, but flowering may be reduced in low light conditions. In natural habitats, it grows on exposed ridges and slopes with high light intensity.
Temperature Requirements
This plant is native to high elevation sites in the Hawaiian Islands, where temperatures are cooler than in the lowland areas. Dubautia scabra var. leiophylla prefers cool temperatures and can tolerate temperatures ranging from 50°F to 75°F (10°C to 24°C). However, it cannot tolerate freezing temperatures or extreme heat.
Soil Requirements
The plant prefers well-drained, acidic soils with a pH range of 4.5 to 5.5. It can grow in various soil types like loamy, sandy, or volcanic soil. In its natural habitat, it is often found in soils that are rich in organic matter and nutrients, but it can also adapt to nutrient-poor soils.
Cultivation Methods for Dubautia scabra (DC.) Keck var. leiophylla (Gray) Keck
Dubautia scabra (DC.) Keck var. leiophylla (Gray) Keck is a plant that is best grown in a greenhouse or under controlled conditions. For outdoor cultivation, it prefers moist, well-draining soil with a pH range of 5.5 to 6.5. The plant should be placed in a location that receives morning sun and afternoon shade to prevent excessive heat and dryness.
Watering Needs for Dubautia scabra (DC.) Keck var. leiophylla (Gray) Keck
Dubautia scabra (DC.) Keck var. leiophylla (Gray) Keck requires moderate watering. The soil should be kept moist but not waterlogged, as excessive moisture can lead to root rot. Watering should be done in the morning or evening, and not during the hottest part of the day to prevent wilting due to excessive transpiration.
Fertilization for Dubautia scabra (DC.) Keck var. leiophylla (Gray) Keck
Dubautia scabra (DC.) Keck var. leiophylla (Gray) Keck requires moderate fertilization. Fertilizer should be applied during the growing season (spring and summer) using a balanced, time-release fertilizer. The recommended dosage is 1/2 to 1 teaspoon per gallon of water every 2-4 weeks. However, for mature plants, it is best to use a formula with a higher percentage of phosphorus to encourage blooming.
Pruning for Dubautia scabra (DC.) Keck var. leiophylla (Gray) Keck
Dubautia scabra (DC.) Keck var. leiophylla (Gray) Keck requires light pruning to maintain its shape and size. Pruning should be done in the spring months when new growth starts. Dead, damaged, or diseased branches or leaves should be removed immediately to prevent the spread of disease. Pinching out the tips of the branches or trimming them lightly will promote bushier growth and encourage the development of more flower buds.
Propagation of Dubautia scabra var. leiophylla
Dubautia scabra var. leiophylla, commonly known as Na'ena'e, is a shrub endemic to the Hawaiian Islands and is a member of the Asteraceae family. Propagation of this plant can be done through several methods:
Seed Propagation
The easiest and most common method of propagating Dubautia scabra var. leiophylla is through seed propagation. The seeds are small, black, and have a fine, silky structure that aids in their dispersal by wind. They should be collected when they are fully ripe and then stored in a cool and dry place until they are ready to be sown.
Seed germination of Dubautia scabra var. leiophylla can be improved by a pre-treatment of cold stratification, usually for 30-60 days at 5°C. The seeds should then be sown in a well-draining potting mix and kept moist until germination occurs, which can take up to several weeks.
Cutting Propagation
Dubautia scabra var. leiophylla can be propagated through stem cuttings as well. This method is useful for propagating individual plants that have desirable characteristics or for producing a large number of plants in a short amount of time. Cuttings should be taken from semi-hardwood stems during the growing season (spring-summer) and should be 4-6 inches in length.
The cuttings should then be treated with a rooting hormone and placed in a well-draining potting mix. They should be kept in a warm and moist environment until new growth emerges from the roots, which can take several weeks to several months.
Division Propagation
Division propagation is another method that can be used to propagate Dubautia scabra var. leiophylla. This method is useful for established plants that have become large and crowded. The plant should be carefully dug up and then divided into several smaller sections, each with its own root system.
The divided sections should then be planted in well-draining soil and kept moist until new growth emerges, which can take several weeks to several months. This method is best done in the spring when the plant is actively growing.
Disease Management
Dubautia scabra (DC.) Keck var. leiophylla (Gray) Keck is known to be susceptible to a few fungal diseases such as powdery mildew, leaf spot, and rust. Powdery mildew may appear as a white or grayish powder on the leaves, while leaf spot and rust can cause discolored spots on the foliage. These diseases can be managed through the following measures:
- Plant the Dubautia scabra (DC.) Keck var. leiophylla (Gray) Keck in well-draining soil and provide adequate air circulation
- Water the plant at the base to avoid getting the leaves wet
- Remove any infected leaves immediately and dispose of them in the trash
- Apply fungicides like neem oil or copper-based fungicides as a preventive measure or as soon as the disease is detected
Pest Management
Dubautia scabra (DC.) Keck var. leiophylla (Gray) Keck is relatively pest-free, but it may occasionally be attacked by spider mites or aphids. These pests can cause wilting, yellowing, or curling of the leaves. To manage pest infestations:
- Regularly inspect the plant for signs of pest infestation
- Wash off any visible pests with a strong jet of water
- Apply insecticidal soap or neem oil to control the pests
- Introduce natural enemies like ladybugs or lacewings to control the pest population
