Ormocarpum sennoides (Willd.) DC. subsp. hispidum (Willd.) Brenan & J.Léonard
Ormocarpum sennoides, commonly known as the "nearly wild laburnum," is a species of flowering plant in the family Fabaceae. It is native to Africa, including Angola, Botswana, Malawi, Mozambique, Namibia, South Africa, Swaziland, Zambia, and Zimbabwe.
The plant is also known by various common names in different regions, such as "bitterwortel," "bitterwort," "bitterhout," "omusirie," and "kakutshane."
Ormocarpum sennoides is a woody shrub or small tree that can reach up to 5 meters in height. It has a single or multiple stems that are grey or brownish in color, with a rough, furrowed texture. The leaves are alternate, pinnately compound, and up to 15 cm long, with 5-11 leaflets. The leaflets are oblong or elliptical and have a hairy texture on the underside.
The plant produces yellow, pea-shaped flowers in large clusters at the ends of the branches. The flowers are followed by elongated pods that can be up to 30 cm long and 2 cm wide. The pods contain numerous seeds that are oval in shape and have a brownish color.
Ormocarpum sennoides has several medicinal uses in traditional African medicine. The roots are used to treat stomach problems, including diarrhea, dysentery, and constipation. The bark and leaves are used to treat fever, coughs, and inflammation. The plant also has pesticidal properties and is used to control insects and pests in crops.
Light Requirements
Ormocarpum sennoides subsp. hispidum typically grows in full sun to partial shade. It is adapted to a range of light conditions, but prefers partial shade in hotter climates to avoid excessive water loss.
Temperature Requirements
Ormocarpum sennoides subsp. hispidum is a tropical plant that prefers warm temperatures. It grows best in temperatures that range from 25-30 °C (77-86 °F). It cannot tolerate frost or cold temperatures below 10 °C (50 °F).
Soil Requirements
Ormocarpum sennoides subsp. hispidum is a versatile plant that grows in a variety of soil types, but prefers well-drained soils with pH levels between 5.5 and 6.5. It does not tolerate water-logged or compacted soils, as this can lead to root rot. It thrives in sandy loam, loam, and clay loam soils with good organic matter content.
Cultivation
Ormocarpum sennoides subsp. hispidum is a fairly easy plant to cultivate and can be grown both indoors and outdoors in suitable climates. It prefers well-draining soil and full-sun exposure for optimal growth, but can tolerate partial shade.
The plant can be propagated from seeds, cuttings, or division. Sow seeds in well-draining soil and keep them moist until germination. Cuttings should be taken during the active growing season and treated with rooting hormone before being planted in well-draining soil.
Watering Needs
The Ormocarpum sennoides subsp. hispidum prefers moderate watering. It should be watered only when the soil in the pot dries out. Overwatering can lead to root rot, so make sure the soil is not excessively damp. On the other hand, under-watering can also be harmful, especially during the plant's growing period in the summer months. Thus, it is important to maintain a moderate watering routine.
Fertilization
The Ormocarpum sennoides subsp. hispidum requires regular fertilization during the growing season to promote healthy growth. A balanced, slow-release fertilizer should be applied once a month to the soil around the base of the plant. Organic compost can be added to the soil to improve its fertility and provide essential nutrients to the plant.
Pruning
Pruning is not necessary for the Ormocarpum sennoides subsp. hispidum, but it can be done during the plant's dormant period to maintain its shape and promote growth in the spring. Dead or damaged branches should be pruned immediately to prevent them from draining energy from the plant. It is best to use a sharp, clean pair of pruning shears to make clean cuts and avoid damaging the plant.
Propagation of Ormocarpum sennoides subsp. hispidum
Ormoacarpum sennoides subsp. hispidum can be propagated through both seeds and cuttings.
Propagation through seeds
The seeds of Ormocarpum sennoides subsp. hispidum are small and should be sown in a well-draining soil mix. Before planting, the seeds should be soaked in water for 24 hours to soften their hard seed coat. Seeds can be sown directly into pots or seed trays and covered lightly with soil. The germination rate of the seeds is usually high, and seedlings should emerge within 2-3 weeks.
Propagation through cuttings
Ormocarpum sennoides subsp. hispidum can also be propagated through stem cuttings. Semi-hardwood cuttings taken in summer will root readily. The cuttings should be taken from the current season's growth and should be approximately 10-15 cm long. The lower leaves should be removed, and the base of the cutting should be dipped in rooting hormone before being placed in a well-draining potting mix. The cuttings should then be covered with a plastic bag or placed in a propagator to maintain a humid environment. Rooting should occur within 4-6 weeks.
Disease Management
Ormomcarpum sennoides subsp. hispidum is relatively resistant to most common diseases. However, in some cases, it can be susceptible to certain fungal and bacterial infections that can severely damage the plant.
Fungal diseases:
Leaf spot disease caused by fungus can occur in humid conditions. The infected plant shows small brown spots with yellow margins that eventually lead to defoliation. Management involves maintaining good air circulation and avoiding overhead watering. Applying fungicides containing copper or other organic compounds can also be effective.
Bacterial diseases:
Bacterial leaf blight can cause serious damage to the plant by causing defoliation. The infected leaves will show water-soaked lesions, which eventually turn brown and dry. Management involves the prompt removal of infected plant parts and the application of copper-based bactericides.
Pest Management
Ormocarpum sennoides subsp. hispidum is vulnerable to some pests like other plants. However, the level of damage caused by these pests is relatively low. Here are some common pests that can affect the growth of this plant and ways to manage them.
Spider mites:
These pests cause discoloration of leaves, webbing, and eventually defoliation. They are common in dry conditions. Management involves monitoring the plants regularly, keeping the plants well-watered to avoid drought stress, and applying insecticidal soap or oil to reduce the population.
Thrips:
Thrips cause damage to new growth by sucking the sap from the plant and causing deformation of leaves. Management involves spraying insecticidal soap or other biocontrol agents like predatory mites and nematodes to reduce the population.
Caterpillars:
The larvae of some moths can cause severe damage to the plant by feeding on the leaves. The management involves handpicking the caterpillars and the application of Bacillus thuringiensis, a biological insecticide that specifically targets caterpillars.
Regular inspection of plants and early intervention can significantly reduce the damage caused by pests and diseases. The use of safer and environmentally friendly management practices is highly recommended.
