Overview
Lobelia deckenii (Ash.) Hemsl. subsp. keniensis (R.E.Fr. & T.C.E.Fr.) E.B.Knox x L. telekii Schweinf. ex Hell. is a rare and stunning plant species that belongs to the Campanulaceae family. It is native to East Africa, and its common names include Telekii Lobelia and Kenyan Lobelia.
Appearance
The Telekii Lobelia is a perennial herb that can grow up to 4 meters tall. It has a unique and remarkable appearance with its palm-like leaves that are divided into narrow, long, and toothed leaflets. This plant also has large and showy flowers that form a spike-like inflorescence.
Uses
The Telekii Lobelia has essential ecological functions as its long-tubed, bright blue flowers attract pollinators like sunbirds. In addition, it plays a vital role in the traditional medicine of East Africa, where different parts of the plant are used to treat various ailments like stomach aches, skin infections, and respiratory problems. Despite its medicinal value, the plant has limited commercial use and is mainly grown as an ornamental plant for its unique beauty.
Cultivation
The Telekii Lobelia grows best in shade or partial shade and thrives in moist, well-drained soils. It is not a hardy plant and is susceptible to frost damage. Therefore, it requires protection from extreme weather conditions. This plant is propagated by seeds and cuttings, but its cultivation is mostly restricted to botanic gardens and specialized nurseries.
Growth conditions for Lobelia deckenii subsp. keniensis x L. telekii
Light: Lobelia deckenii subsp. keniensis x L. telekii typically grows in full sun or partial shade. In their natural habitat, these plants are adapted to high elevations where the sunlight is often intense. Hence, it is important to provide them with ample light to thrive.
Temperature: These plants thrive in cool to cold temperatures. They are adapted to high elevations and can withstand temperatures as low as -2°C. However, they do not do well in high temperatures above 25°C. Therefore, it is important to maintain a cool environment when growing Lobelia deckenii subsp. keniensis x L. telekii.
Soil Requirements: Lobelia deckenii subsp. keniensis x L. telekii grows well in well-draining soil. They are mostly found growing on rocky slopes with well-draining soils that are rich in organic matter. The soil should be moist, but not waterlogged, as excessive moisture can cause root rot.
Water: These plants require regular watering and thrive in a moist environment. However, it is crucial to avoid waterlogging the soil as this can cause root rot. It's always a good idea to water these plants when the top inch of soil is dry.
Fertilizer: Lobelia deckenii subsp. keniensis x L. telekii benefits from regular fertilization during the growing season. A balanced fertilizer with equal amounts of nitrogen, phosphorus, and potassium can be applied every four to six weeks. However, it's important to avoid over-fertilization, which can result in excessive growth and weak stems.
Propagation: These plants can be propagated from seed and cuttings. Seeds should be sown in well-draining soil and kept moist until they germinate. Cuttings should be taken during the growing season and rooted in moist soil. It's important to avoid over-watering when propagating Lobelia deckenii subsp. keniensis x L. telekii, as this can cause root rot.
Cultivation Methods for Lobelia Deckenii subsp. Keniensis
Lobelia Deckenii subsp. Keniensis is a difficult plant to cultivate, which requires some knowledge and attention. It is best to grow it in containers to ensure better environmental control. The container should be at least 10 inches deep and wide, and have good drainage holes.
The plant thrives in a well-draining soil mix, which should be rich in organic matter. A suitable mix can be prepared by combining equal parts of peat, perlite, and coarse sand. The soil should be slightly acidic, with a pH range of 5.5 to 6.5.
Watering Needs for Lobelia Deckenii subsp. Keniensis
Lobelia Deckenii subsp. Keniensis requires consistent moisture to thrive. The soil should be kept moist, but not waterlogged, at all times. The plant prefers moderate to high humidity levels, and it is important to mist it regularly.
Watering frequency will depend on the environmental conditions, but it is recommended to water the plant once or twice a week, depending on the soil moisture level. To avoid overwatering, it is important to ensure that the soil has good drainage.
Fertilization for Lobelia Deckenii subsp. Keniensis
Lobelia Deckenii subsp. Keniensis benefits from regular fertilization during the growing season. A well-balanced fertilizer with a ratio of 20-20-20 is suitable, and it can be applied once every two weeks. However, it is important to follow the manufacturer's instructions on the application rate.
The plant also responds well to organic fertilizers, such as compost tea or worm castings. These can be applied once a month as a supplement to the regular fertilizer.
Pruning for Lobelia Deckenii subsp. Keniensis
Lobelia Deckenii subsp. Keniensis does not require extensive pruning, but it benefits from regular pinching to promote bushier growth. Pinching can be done by removing the tips of the stems, using clean and sharp scissors.
The plant may also need occasional pruning to remove any dead or damaged foliage, or to control its size and shape. Pruning should be done during the growing season, and it is important to avoid cutting into old wood, as this may prevent the plant from regenerating.
Propagation of Lobelia deckenii subsp. keniensis x L. telekii
Lobelia deckenii subsp. keniensis x L. telekii can be propagated through various methods such as division, cuttings, and seed propagation. Each method has its own unique requirements and benefits.
Division
Division is the process of separating the plant into smaller parts, and each part will grow into a new plant. This propagation method is best used for mature plants that have developed a good root system. To propagate Lobelia deckenii subsp. keniensis x L. telekii using division, carefully dig up the plant and separate the plant into smaller sections, making sure each section has enough roots and leaves. Each section can then be planted in a new pot or directly in the ground. Division can be done in the early spring when new growth appears, or in the fall before the plant goes dormant.
Cuttings
Cuttings involve taking a stem or leaf cutting from a parent plant and placing it in a rooting medium to develop roots and grow into a new plant. This method is ideal for plants that may not have a well-established root system yet. To propagate Lobelia deckenii subsp. keniensis x L. telekii through cuttings, select a healthy parent plant and take a stem cutting, making sure to include a node. Dip the cut end in rooting hormone before planting it in sterile soil or a rooting medium. Keep the cutting in a warm and humid environment and ensure it receives adequate light and water. In a few weeks, new growth should appear, indicating that roots have formed.
Seed Propagation
Seed propagation is the process of growing a new plant from a seed. This propagation method is best used for new plants, as it takes longer to establish than the other methods. To propagate Lobelia deckenii subsp. keniensis x L. telekii through seed propagation, collect mature seeds from a parent plant and plant them in well-draining, fertile soil. Keep the soil consistently moist and at a warm temperature. The seeds should germinate within 2-4 weeks. Once the seedlings have grown and developed several leaves, they can be transplanted into pots or directly into the ground.
Disease Management
One of the common diseases that can affect Lobelia deckenii subsp. keniensis x L. telekii is leaf spot. This disease is characterized by the appearance of circular spots on the leaves that gradually expand and turn brown. To manage leaf spot, it is important to practice good hygiene by removing infected leaves and destroying them. Additionally, avoiding overhead watering can prevent the spread of the disease.
Another disease that can affect this plant is powdery mildew. This disease is characterized by the appearance of a white, powdery substance on the leaves and stems. To manage powdery mildew, it is important to keep the foliage dry and to provide good air circulation around the plant. Additionally, applying fungicides can help control the disease.
Pest Management
One of the common pests that can affect Lobelia deckenii subsp. keniensis x L. telekii is the aphid. These small insects feed on the sap of the plant and can cause stunted growth, yellowing leaves, and distorted growth. To manage aphids, it is important to encourage natural predators such as ladybugs and lacewings. Additionally, applying insecticidal soap or neem oil can help control aphids.
Another pest that can affect this plant is the spider mite. These tiny pests feed on the underside of leaves and can cause yellowing and browning of the foliage. To manage spider mites, it is important to keep the foliage clean and dry and to provide good air circulation around the plant. Additionally, applying insecticidal soap or neem oil can help control spider mites.
