sawtooth coriander mexican culantro seeds Culantro Seeds Long Coriander Thai Parsley Seeds Culantro spiritweed seeds. The plant thrives best in well irrigated shaded conditions. Shaded areas produce larger and greener leaves with a better appearance and higher pungent aroma. Duck-Tongue herb, Sawtooth, or Saw-Leaf herb, Coriander Herb Seeds Recao Sawtooth Mexican Coriander Herb Seeds. Learn how to grow culantro, a pungent herb used in Latin American and Asian cuisines. Find out the difference between culantro and cilantro, the best growing conditions, and the medicinal benefits of culantro. Culantro is a biennial herb grown as an annual that is indigenous to the American tropics and West Indies. Culantro is easy to grow but needs attention and patience to be successful with. Three critical conditions are warm soil - 80-85°F, seeds on the surface of the soil – never covered, and a consistently moist soil