Jatropha curcas, commonly known as Physic Nut or Barbados Nut, is a semi-evergreen shrub native to the tropical Americas, highly valued for biodiesel production and traditional medicinal uses. Seed germination exhibits primary dormancy and can be erratic even under optimal conditions, with variability influenced by seed age, storage conditions, and cultivar. The species is drought-tolerant and adaptable to poor soils, making it economically important for arid and semi-arid regions.
Before sowing
Seeds are oily and exhibit primary dormancy. Intervals of presoaking and drying, or partial removal of seed coat are more successful than presoaking alone. Avoid extended acid or high temperature treatments which can reduce viability.
Sowing
What to expect
Tips
Use fresh seeds whenever possible as seed viability declines significantly after 12-15 months of storage. Keep soil moisture moderate—neither waterlogged nor dry. Warm temperatures (25-30°C) strongly favor germination. Store seeds at 4°C with 7-8% moisture content for optimal long-term viability. Avoid adding manure during germination, as it inhibits seedling development. Germination is typically complete within 9 days under favorable conditions, though some seeds may take up to 15 days or longer.
Sources: Wikipedia (Jatropha curcas), World Agroforestry Centre (ICRAF), Sheffield's Seed Company, Infonet Biovision, MDPI Biomolecules, ResearchGate, SciELO Brazil, scientific literature on Jatropha seed germination
