Ornamental Grass Growth Response to Three Shade Intensities

Growth of perennial quaking grass (Briza media L.), ‘Red Baron’ Japanese bloodgrass (Imperata cylindrica (L.) Beauv. ‘Red Baron’), river oats (Chasmanthium latifolium (Michx.) Yates), ‘Hameln’ dwarf fountain grass (Pennisetum alopecuroides (L.) Spreng. ‘Hameln’), and ‘Big Blue’ monkeygrass (Lirope muscari (Decne.) L.H. Bail. ‘Big Blue’) in 0%, 30%, or 60% shade was evaluated in container and in-ground experiments conducted over two growing seasons. Shade intensity did not affect plant height of any species grown in containers in 1997 or those grown in the ground that were planted and harvested in 1998. In 1997, width of containerized perennial quaking grass increased and width of containerized dwarf fountain grass decreased with increasing shade. In 1998, width of containerized Japanese bloodgrass increased and width of containerized dwarf fountain grass decreased with increased shade. Container-grown river oats shoot and root dry weight increased with shade intensity in 1998. Root to shoot (R/S) ratio decreased linearly with shade intensity for containerized river oats in 1997. Height of in-ground Japanese bloodgrass was not affected by shade intensity at any harvest time; however, height of perennial quaking grass increased and height of river oats and monkeygrass decreased as shade intensity increased regardless of harvest time. Few differences in plant width among shade treatments occurred for in-ground plants. Shoot dry weights for in-ground plants generally decreased with increasing shade intensity. Climatic differences may account for the variability in plant growth between the two years of the study.