Submitted to: HortTechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/4/2003
Publication Date: 12/5/2003
Citation: Kleitz, K.M., Wall, M.M., Falk, C.L., Martin, C.A., Remmenga, M.D., Guldan, S.J. 2003. Yield potential of selected medicinal herbs grown at three plant spacings in New Mexico. HortTechnology. 13(4):631-636. Interpretive Summary: Medicinal herbs are being tested on small farms in New Mexico as high-value crop alternatives, but limited production information is available to growers. The purpose of this study was to determine the production potential of selected medicinal herbs (echinacea, valerian, mullein and yerba mansa) grown at three plant densities in southern and northern New Mexico. All crops at both sites had greatest yields at the highest plant density tested (about 36,000 plants/ha). Higher plant densities may increase yields further. Economic analyses conducted on these herbs indicate that New Mexico farmers could grow echinacea profitably in a significant portion of the state. Northern New Mexico farmers could grow valerian profitably, while southern New Mexico farmers could grow yerba mansa.
Technical Abstract: Field studies were conducted to determine the production potential of echinacea (Echinacea purpurea), valerian (Valeriana officinalis), mullein (Verbascum thapsus) and yerba mansa (Anemopsis californica) medicinal herbs at two sites in New Mexico. Las Cruces, N.M. is at an elevation of 1,186 m and has an average of 220 frost free days per year, whereas Alcalde, N.M. is at an elevation of 1,730 m and averages 152 frost-free days per year. In-row plant spacings of 30, 45, and 60 cm were compared at both locations. The corresponding plant densities for the 30, 45 and 60 cm spacings were 35,879 plants/ha, 23,919 plants/ha, and 17,940 plants/ha, respectively. Data were collected on growth rates, fresh yield, and dry yield for the herbs grown at each site. All crops at both sites had highest yields at the 30 cm spacing, suggesting that optimum in-row plant spacings are at or below the 30 cm spacing. Yields of 4.35 t ha-1 of dried yerba mansa root, 2.22 t ha-1 of echinacea root, and 5.15 t ha-1 of dried mullein leaves were realized at the 30 cm spacing at Las Cruces in southern New Mexico. Yields of 2.60 t ha-1 of dried valerian root, 2.08 t ha-1 of dried echinacea root, and 1.14 t ha-1 of dried mullein leaves were harvested at the 30 cm spacing at Alcalde in northern New Mexico. Yields of fresh echinacea flowers were 3.5 t ha-1 in Las Cruces. Yields of dried mullein flowers were 1.52 t ha-1 in Las Cruces and 1.48 t ha-1 in Alcalde.