The jatropha curcus plant is a small shrub believed to have originated in Mexico and Central America, but is now cultivated throughout the world and particularly in India, where the plant is grown as a cash crop. This rugged, drought-resistant perennial is fast-growing and lives for 50 years, producing seed the entire time. The oil contained in the seeds can be combusted as fuel without any refinement and burns with clear smoke-free flame. Scientists have found the jatropha seed oil to be successful as fuel for simple diesel engines.
The jatropha plant is also easy to propagate and thrives in arid and semi-arid climates, but is most successful in drier regions of the tropics at lower altitudes with average temperatures well above 68 degrees Fahrenheit.
Plant your jatropha bush in low-nutrient, well-drained soil. The jatropha will grow and thrive in a wide range of poor-quality soils, including sandy, saline and even gravelly soils. However, the plant does prefer soil with a lot of earthworm activity, as this increases the soil's fertility and oxygen to the plant's roots.
Plant the seeds 1 1/2 inches down into the soil, if you're growing your jatropha plant from seed. Use a well-draining potting mix. Barely moisten the soil.
Grow your jatropha in a hot, dry environment. Although jatropha plants can withstand lower temperatures and even a slight frost, they prefer warmer climatic conditions that resemble the tropic and sub-tropic regions.
Position the jatropha plant in full sunlight. Water your jatropha sparingly, giving it only enough water to slightly dampen the soil.
Look for the inedible fruits on the jatropha in winter when the shrub is leafless. Each inflorescence grows a cluster containing 10 or more fruits. Harvest the seeds approximately three months after the jatropha flowers. The seeds are mature after two to four months, when the outer capsule turns from green to yellow.
Allow the jatropha's leaves to remain on the ground after it sheds them during winter. Don't clean up the leaves or remove them. These shed leaves form a sort of mulch layer around the plant's base and attract earthworms toward the roots.