Pruning should be done once a year. Lateral shoots are requisite for maximum sprouting flowers and seed production (Gour 2006). Pruning is very essential as it determines seed yield to a large extent and can facilitate mechanical and manual harvesting of fruits. Number of flowering branches is determined by canopy size. Sufficient flowering branches can result apparently from smaller plants on high den­sities and large plants on a low planting density (Daey Ouwens et al. 2007). Ideal time for pruning is during dry season when the tree enters a period of dormancy and sheds its leaves (Kaushik et al. 2007).

17.3.4 Weed Control

Weeding is an important issue particularly during early stages of plant growth as it reduces competition for acquiring nutrients. Weeding can be done either by apply­ing herbicides or by soil surface plowing. The most common herbicides used are oxyfluorfen and pendimethalin (Rocha 2010). Number of times weeding should be performed mainly depends on the season and field conditions with four times a year being ideal. Fertilization, pruning, and regular weeding are hence important cultural practices in new plantations (Henning 2007).

17.3.5 Harvesting

Jatropha becomes highly productive in 4-5 years time. Flowering mainly depends on agro-climatic conditions and location. Generally, flowers are produced in first 16-17 weeks by cloned Jatropha seedlings. Once mature, Jatropha fruits can be harvested mechanically which has several benefits, such as continuous and selective harvesting, labor reduction, cost control, on demand harvest ability and reliability and efficiency.