Origin
Hypericum revolutum Vahl subsp. keniense (Schweinf.) N.Robson is a species of flowering plant that belongs to the Hypericaceae family. This subspecies is native to the high mountains of East Africa, specifically found in Kenya and Tanzania.
Common Names
Hypericum revolutum Vahl subsp. keniense commonly goes by the name of "Kenyan St. John's Wort" or "Kenyan Hypericum". The plant is referred to as such because it bears some resemblance to the medicinal plant St. John's Wort.
Uses
The Kenyan St. John's Wort plant has been used for traditional medicinal purposes by the local communities for decades. Its leaves, stems and seeds are believed to have therapeutic effects against various ailments such as colds, fever, dysentery, and asthma. The leaves are sometimes crushed and blended with animal fat to create an ointment that can be applied topically to soothe skin irritations and wounds. Additionally, the plant is also a popular ornamental plant because of its beautiful golden yellow flowers.
General Appearance
The Kenyan St. John's Wort is an erect or sometimes decumbent shrub that can grow up to 2 meters tall. It has a woody stem and branches with small green leaves that are arranged oppositely along the stem. The leaves are mostly obovate, with pointed tips and wavy margins. The flowers are bright yellow in colour and have five petals with numerous yellow stamens. The fruits are capsules with numerous small seeds. Overall, the plant has a bright and cheerful appearance that impresses many plant enthusiasts.
Light Requirements
Hypericum revolutum Vahl subsp. keniense (Schweinf.) N.Robson plants require full sun for optimal growth. These plants grow best in areas that receive at least 6 hours of direct sunlight per day. However, they can tolerate some shade as long as they get enough light to develop adequately.
Temperature Requirements
Hypericum revolutum Vahl subsp. keniense (Schweinf.) N.Robson plants grow best in tropical to subtropical climates with warm temperatures. The optimal temperatures for growth are between 20°C to 30°C. They can withstand occasional temperature fluctuations of up to 35°C, but prolonged exposure to high temperatures can cause heat stress and damage the plant.
Soil Requirements
Hypericum revolutum Vahl subsp. keniense (Schweinf.) N.Robson plants grow well in well-draining and nutrient-rich soils. The ideal soil for these plants is sandy or loamy, with a pH of 6.0 to 7.5. It is crucial to avoid waterlogged soils, as this can cause root rot and other diseases that can affect plant growth. To improve soil fertility, it is recommended to supplement it with organic matter such as compost or manure.
Cultivation methods
Hypericum revolutum Vahl subsp. keniense (Schweinf.) N.Robson, commonly known as the Kenyan St. John's Wort, is a shrub that grows best in well-drained soil under partial shade. The plant can tolerate high temperatures and humidity, but it cannot withstand frost. When planting, place the plant in a hole that is twice the width of its container and at the same level as the soil surface. Water the plant thoroughly after planting and regularly thereafter until it is established.
Watering needs
The Kenyan St. John's Wort requires moderate watering, which means that the plant should receive enough water to keep the soil moist but not soggy. During the growing season, water regularly, especially during periods of high temperatures or drought. Avoid watering the plant from overhead as this can lead to foliar diseases. Instead, use a soaker hose that directs water to the plant's base.
Fertilization
Feed the Kenyan St. John's Wort with a balanced fertilizer during the growing season. Apply the fertilizer at half strength to avoid over-fertilization, which can cause the plant to produce excessive foliage at the expense of flowers. Mulch the plant with organic matter such as compost or well-rotted manure to improve soil fertility and moisture retention.
Pruning
The Kenyan St. John's Wort requires minimal pruning, but it may be pruned to maintain its form or to remove dead or damaged branches. Prune the plant in late winter or early spring, before new growth appears. Use sharp, clean pruning shears to avoid damaging the plant's stems. If the plant becomes too leggy or overgrown, it can be cut back hard to about one third of its height to rejuvenate it.
Propagation of Hypericum revolutum Vahl subsp. keniense (Schweinf.) N.Robson
Hypericum revolutum Vahl subsp. keniense (Schweinf.) N.Robson is a woody shrub native to Kenya and Tanzania. The plant is propagated through various methods, including seed propagation, cutting, and division.
Seed Propagation
Hypericum revolutum Vahl subsp. keniense (Schweinf.) N.Robson can be propagated through seeds. The seeds should be sown in well-draining soil in a pot or a seed tray. The pot or the tray should be kept in a warm and sunny location with consistent moisture. The seeds can take up to four weeks to germinate, and once the seedlings are established, they can be transplanted to a larger pot or planted outdoors.
Cutting Propagation
Hypericum revolutum Vahl subsp. keniense (Schweinf.) N.Robson can also be propagated through cuttings. The best time to take cuttings is during the growing season when the plant is actively growing. Cut a stem that is approximately 10 cm in length, remove the leaves from the bottom half of the stem, and dip the end in rooting hormone. Plant the cutting in well-draining soil and keep it in a warm and sunny location with consistent moisture. The cutting should start developing roots in two to three weeks, and once the roots are established, the cutting can be transplanted to a larger pot or planted outdoors.
Division Propagation
Hypericum revolutum Vahl subsp. keniense (Schweinf.) N.Robson can also be propagated through division. The plant should be lifted from the ground and cleaned of any excess soil. The root system can then be divided into smaller sections, each with its own stem and leaves. The smaller sections can be replanted in well-draining soil and kept in a warm and sunny location with consistent moisture. The plant should start developing new growth in a few weeks, and once established, it can be planted outdoors.
Disease Management
The plant Hypericum revolutum Vahl subsp. keniense (Schweinf.) N.Robson is susceptible to various diseases. Here are some common diseases and ways to manage them:
- Anthracnose: This disease is characterized by brown spots that have a purple border. It can be managed by removing infected plant parts and disposing of them properly. Avoid overhead watering, which contributes to the spread of the disease. Fungicides can also be used to manage the disease.
- Powdery Mildew: This fungal disease appears as white powder on the leaves. It can be managed by pruning affected plant parts and increasing air circulation around the plant. Fungicides can also be used to manage the disease.
- Root Rot: This disease is caused by soil-borne pathogens and can result from overwatering or poor soil drainage. Plants affected by root rot should be removed and destroyed. To prevent root rot, ensure that the soil is well-draining and water the plant only when necessary.
Pest Management
The plant Hypericum revolutum Vahl subsp. keniense (Schweinf.) N.Robson is also vulnerable to various pests. Here are some common pests and ways to manage them:
- Aphids: These small insects feed on the plant's sap, resulting in stunted growth and distortion of the leaves. They can be managed by spraying the plant with water to dislodge the insects or using insecticidal soap or neem oil.
- Spider Mites: These tiny pests also suck the plant's sap and cause discoloration and curling of leaves. They can be managed by increasing humidity around the plant and using insecticidal soap or neem oil.
- Whiteflies: These insects feed on the plant's sap and excrete a sticky substance called honeydew, which attracts ants and promotes the growth of sooty mold. They can be managed by using insecticidal soap or neem oil.
