Juniperus virginiana as an Alternative to Pine Bark in Nursery Production

Abstract

Pine bark has been the standard container nursery substrate for nearly forty years. However, due to the decline in the timber industry and fluctuations in fuel prices, alternative substrates and amendments are being sought by growers and researchers. This study evaluated locally grown eastern red cedar (Juniperus virginiana L.) as a potential alternative to pine bark in nursery production of 10 ornamental species. For seven of the species evaluated, growth indices for plants in 100% cedar were similar to those in 100% pine bark. ‘August Beauty’ gardenia grown in up to 80% cedar was comparable to plants grown in pine bark. Species that have lower pH requirements did not perform as well in substrates amended with high cedar percentages. ‘Premier’ blueberry did not grow well in cedar above 20%. Root growth for seven of the species in cedar was similar to or greater than those grown in 100% pine bark. ‘Formosa’ azalea and ‘Burgundy’ loropetalum showed slight variations in root growth above 10% cedar. These data conclude that cedar has potential as an amendment to pine bark in nursery production.