Aeroponic and Hydroponic Systems for Medicinal Herb, Rhizome, and Root Crops

Hydroponic and aeroponic production of medicinal crops in controlled environments provides opportunities for improving quality, purity, consistency, bioactivity, and biomass production on a commercial scale. Ideally, the goal is to optimize the environment and systems to maximize all five characteristics. Examples of crop production systems using perlite hydroponics, nutrient film technique (NFT), ebb and flow, and aeroponics were studied for various root, rhizome, and herb leaf crops. Biomass data comparing aeroponic vs. soilless culture or field grown production of burdock root (Arctium lappa), stinging nettles herb and rhizome (Urtica dioica), and yerba mansa root and rhizome (Anemopsis californica) are presented, as well as smaller scale projects observing ginger rhizome (Zingiber officinale) and skullcap herb (Scutellaria lateriflora). Phytochemical concentration of marker compounds for burdock and yerba mansa in different growing systems are presented.

Yield Potential of Selected Medicinal Herbs Grown at Three Plant Spacings in New Mexico

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 3,891 ft (1,186 m) and has an average of 220 frost free days per year, whereas Alcalde, N.M., is at an elevation of 5,719 ft (1,743 m) and averages 152 frost-free days per year. In-row plant spacings of 12, 18 and 24 inches (30.5, 45.7, and 61.0 cm) were compared at both locations. The corresponding plant densities for the 12, 18 and 24 inch spacings were 14,520 plants/acre (35,878 plants/ha), 9,680 plants/acre (23,919 plants/ha), and 7,260 plants/acre (17,939 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 plot yields at the 12-inch spacing, suggesting that optimum in-row plant spacings are at or below the 12-inch spacing. Yields of 1.94 ton/acre (4.349 t·ha-1) of dried yerba mansa root, 0.99 ton/acre (2.219 t·ha-1) of dried echinacea root, and 2.30 ton/acre (5.156 t·ha-1) of dried mullein leaves were realized at the 12-inch spacing at Las Cruces in southern New Mexico. Yields of 1.16 ton/acre (2.600 t·ha-1) of dried valerian root, 0.93 ton/acre (2.085 t·ha-1) of dried echinacea root, and 0.51 ton/acre (1.143 t·ha-1) of dried mullein leaves were harvested at the 12-inch spacing at Alcalde in northern New Mexico. Yields of fresh echinacea flowers were 1.56 ton/acre (3.497 t·ha-1) in Las Cruces. Yields of dried mullein flowers were 0.68 ton/acre (1.524 t·ha-1) in Las Cruces and 0.66 ton/acre (1.479 t·ha-1) in Alcalde.

Nutrient and heavy metal uptake and storage in constructed wetland systems in Arizona

The Constructed Ecosystems Research Facility (CERF) was conceived in the early 1980s as a test facility to explore the potential for using plants to treat wastewater in the arid west of the USA. One of the major issues that has been identified in the use of constructed wetland technology is plant nutrient uptake and tissue storage of nutrients as well as heavy metals. Our approach to understanding plant uptake and storage has been to look at both controlled conditions in constructed systems and background concentrations in natural systems. Plant tissues have been collected and analyzed from natural systems and from controlled systems receiving either wastewater or municipal water. Plants studied included the herbaceous species Anemopsis californica (Yerba mansa), Scirpus spp. (bulrush) and Typha domingensis (cattail), and tree species Fraxinus velutina (ash), Populus fremontii (cottonwood) and Salix spp. (willow). Data indicate that uptake varies not only among plant species, but also among chemical species, depending upon water quality within the wetlands. Leaf tissues of Fraxinus, Salix and Populus, contained the lowest amounts of nutrients and heavy metals studied (Na, P, K, Cu, Pb and Zn), while the root tissues of the herbaceous plants generally had the highest concentrations.

Costs and Returns of Growing Selected Medicinal Herbs in New Mexico Indicate Positive Return to Land and Risk Likely

Cost and return estimates are presented for selected medicinal herbs grown in a plant-spacing study at two sites in New Mexico. The selected herbs were echinacea [Echinacea purpurea (L.) Moench], valerian (Valeriana officinalis L.), and yerba mansa (Anemopsis californica Nutt.). Significant returns to land and risk were observed in the crops grown at the closest plant spacing, 12 inches (30 cm). Return to land and risk after two growing seasons from echinacea was estimated for a 10-acre (4-ha) farm to be $16,093/acre ($39,750/ha) in Las Cruces and $14,612/acre ($36,092/ha) in Alcalde.