Gaura Lindheimeri Research Articles

345 Incorporation of Slow-release Fertilizer Accelerates Growth during Adventitious Rooting of Artemisia, Gaura, and Nepeta

Accelerating growth of nursery stock can produce marketable plants in less time, thus potentially increasing profits. The primary objective of this study was to compare adventitious rooting and initial growth of cuttings of three perennials species in response to slow-release fertilizer incorporated into the propagation media. The experiment was a split-plot consisting of four blocks, nine nutrient treatments, three species, and four cuttings per replication within each block-nutrient, species treatment. Treatments consisted of Nutricote 13-13-13 Type 180 and Nutricote 18-6-8 Type 180 incorporated into the rooting media, each at 3, 6, 9, and 12 g·L-1, and a control with no Nutricote. Species studied were Artemisia ludoviciana `Valerie Finnis', Gaura lindheimeri `Whirling Butterflies', and Nepeta ×faassenii `Six Hills Giant'. There were of 144 cuttings per species for a total of 432 cuttings. Fertilizer treatments did not influence rooting percentage, and no significant differences were found between the two formulations of fertilizer for top growth, root growth, rooting percentage, or root number. However, regardless of formulation or rate, the eight fertilizer treatments resulted in greater top and root dry weights when compared to the control. Top and root dry weight increased linearly within both fertilizer formulations.

Growth of Perennials and Leaching of Heavy Metals in Media Amended with a Municipal Leaf, Sewage Sludge and Street Sand Compost

Abstract Municipal leaves, sewage sludge, and street sand were composted by a modified Beltsville aerated pile technique. Rooted cuttings of Aster novi-belgii L. ‘Peter Harrison,’ Gaura Lindheimeri Engelm. & A. Gray and Sedum purpurem (L.) Link ‘Autumn Joy’ were grown for 4 months in 2 1 (2 qt) containers filled with media containing 0, 10, 30, 60, 80 and 100 (percent by vol) compost. The medium with 0% compost contained loamy sand topsoil, peat, sand and Styrofoam pellets (1:5:2:2 by vol). The pH of all media was between 6.0 and 7.0. Half the containers in each treatment received liquid fertilization in mid-season and half did not. Leachate from the containers was collected at monthly intervals and analyzed for the heavy metals Cd, Cr, Cu, Mn, Ni, Pb and Zn to determine their potential for leaching. Growth of perennials was equal or greater in all media containing compost, compared to the medium containing no compost. Liquid fertilizer further improved growth. Adding compost increased media aeration, available plant nutrients and heavy metals and decreased moisture retention and bulk density. Heavy metal concentrations in leachate were low, probably due to the near neutral media pH, and not likely to pose an environmental risk.