Overview
Jatropha hirsuta Hochst. var. oblongifolia Prain is a plant species belonging to the Euphorbiaceae family. It is a small shrub native to India, Pakistan, and Nepal, and widely used in traditional medicinal practices.
Common Names
The plant is commonly known as Wild Castor, Wild Jatropha, and Black Physic Nut.
Appearance
Jatropha hirsuta Hochst. var. oblongifolia Prain is a small, multi-branched shrub that grows up to 2 meters in height. It has light green leaves that are 5-12 cm long and 3-5 cm broad. The plant produces small, greenish-yellow flowers that are about 1 cm in diameter. The fruit is reddish-brown, smooth, and approximately 1 cm in diameter, containing 2-3 seeds.
Uses
The plant has a wide range of medicinal uses, including being used to treat diabetes, inflammation, fever, and skin diseases. The leaves and stem of the plant are used for making poultices, while the root bark is used to make a tea. The seeds produce oil that can be used for making biofuels, soap, and insecticides, as well as being used in folk medicinal practices. It is also used in land restoration practices, as it has been shown to have the ability to grow in degraded soils.
Light Requirements
Jatropha hirsuta Hochst. var. oblongifolia Prain generally prefers bright light and can tolerate full sun conditions as long as the temperature does not exceed the optimal range. It is advisable to provide partial shade to the plant during extremely hot weather conditions or when it is grown in a greenhouse.
Temperature Requirements
The plant can thrive in a wide temperature range. The optimal temperature range for the Jatropha hirsuta Hochst. var. oblongifolia Prain is between 18 to 32 ?. If exposed to temperatures below 10?, the plant may get damaged. Nonetheless, the plant has a remarkable ability to tolerate high temperatures, withstanding up to 50 ?.
Soil Requirements
Well-draining soil with a pH of 6.5-7.5 is ideal for the Jatropha hirsuta Hochst. var. oblongifolia Prain plant. However, it can grow in soils with varying pH levels between 5.5 and 8.5. The soil should be fertile, porous, and rich in organic matter. Clayey and heavy soils are not suitable for the plant. Although it is drought-resistant, the plant requires adequate moisture levels. Excess waterlogging can lead to root rot and the ultimate death of the plant.
Cultivation Method of Jatropha hirsuta Hochst. var. oblongifolia Prain
Jatropha hirsuta Hochst. var. oblongifolia Prain is a drought-resistant plant and can grow in a wide range of soil, from sandy to loamy. It can also tolerate both acidic and alkaline soils. However, it is advisable to plant it in well-draining soil with a pH range of 6.5 to 7.5 for optimal growth. The plant has shallow roots and requires a good amount of sunlight. Therefore, choose a location with adequate sunlight exposure.
Watering Needs of Jatropha hirsuta Hochst. var. oblongifolia Prain
As mentioned, Jatropha hirsuta Hochst. var. oblongifolia Prain is a drought-resistant plant and can survive in dry conditions. It requires regular watering, especially during the first couple of years of growth, to establish its roots. Afterward, it can fend for itself with minimal watering. Water the plant deeply, but do not let the soil become waterlogged. Always ensure the soil is dry before watering again.
Fertilization of Jatropha hirsuta Hochst. var. oblongifolia Prain
The plant requires minimal fertilization and can thrive in nutrient-depleted soils. However, if you want to improve its growth, you may apply a balanced NPK fertilizer once annually. Over-fertilizing the plant is not advisable, as it can lead to excessive growth at the expense of flowering.
Pruning of Jatropha hirsuta Hochst. var. oblongifolia Prain
Jatropha hirsuta Hochst. var. oblongifolia Prain requires minimal pruning. You can remove the dead or damaged branches and shape the plant to your liking. However, avoid excessive pruning, as it can affect the plant's growth and flowering. Prune the plant during the dormant season, preferably in late winter or early spring.
Propagation of Jatropha hirsuta Hochst. var. oblongifolia Prain
The plant can be propagated through various methods, which include:
Seed Propagation
Seeds of Jatropha hirsuta Hochst. var. oblongifolia Prain can be collected from matured fruits. Seeds should be sown in prepared soil in containers or beds during favorable weather conditions.
Seeds should be soaked in water for several hours before sowing, as this helps to promote germination. Seeds can be sown directly into the soil or in germination trays with good drainage. The seedlings should be transplanted to individual containers when they attain two to three true leaves.
Cuttings Propagation
Stem cuttings are another method of propagating the plant. Softwood or semi-hardwood cuttings from healthy plants should be taken during the rainy season or when the plants are actively growing. The stem cuttings should be about 15-20 cm long and be stripped of all the leaves except the top two or three.
After removing the leaves, the cuttings should be planted in prepared soil in polybags or containers and kept moist. The plant should develop a good root system within six to eight weeks, and after this period, it can be transplanted to the field.
Air layering
Air layering is another method of propagation. A branch of the plant in good health is selected, and a portion of the stem c. 5-10 cm long is scraped and treated with rooting hormone.
The scraped portion is wrapped with moist moss and then covered with polythene to create a humid environment. The polythene should be tied firmly above and below the moss to keep it in place. After several weeks, roots will begin to form in the moss. The newly formed roots should be allowed to grow for a few more weeks before the newly propagated plant is detached from the mother plant.
Disease Management
Jatropha hirsuta Hochst. var. oblongifolia Prain is a hardy plant that can resist many diseases. However, some diseases affect the plant, causing damage or even death. One of the common diseases is powdery mildew, which is a fungal infection that appears as grayish-white powdery growth on leaves and stems. The infection can weaken the plant and reduce its yield. To manage powdery mildew, remove and destroy infected plant parts, maintain adequate spacing between plants, and apply fungicides.
Another disease that affects Jatropha plants is leaf spot, which is caused by the fungus Phoma exigua. The disease first appears as tiny black spots on the leaves and gradually spreads to other parts of the plant, causing defoliation. To manage leaf spot, remove and destroy infected plant parts, maintain adequate ventilation around the plant, and apply fungicides.
Pest Management
There are several pests that affect Jatropha hirsuta Hochst. var. oblongifolia Prain, and they include the Jatropha stem borer, aphids, and spider mites. The stem borer is a larva that bores into the stems and causes wilting of the plant. To manage the stem borer, remove and destroy infected plant parts, apply insecticides, and practice crop rotation.
Aphids are small, soft-bodied insects that suck sap from the plant, causing deformities and stunted growth. To manage aphids, use insecticidal soap or neem oil, introduce natural enemies like ladybirds, and maintain good plant hygiene.
Spider mites are tiny insects that suck sap from the plant, causing yellowing, wilting, and webbing on the leaves. To manage spider mites, maintain adequate moisture levels, remove and destroy infected plant parts, and apply insecticidal soap or neem oil.
