Performance of 3 Florida native grasses grown in varying container substrates

Abstract

Demand for native plants in landscape restoration is growing, often surpassing supply, while the cost and sustainability of peat-based container substrates are becoming concerns. This has led to interest in affordable, locally sourced alternatives. In this study, the growth performance of 3 native grasses from the Poaceae family—lopsided Indiangrass (Sorghastrum secundum (Elliott) Nash), wiregrass (Aristida beyrichiana Trin. & Rupr.), and sugarcane plumegrass (Saccharum giganteum (Walter) Pers.)—were evaluated across 4 container substrates. The substrates included 2 commercial mixes (ratio volume/volume), Pro-Mix HP Mycorrhizae (65–75% peat: 25–35% perlite), and Pro-Mix 55BK (55% pine bark: 30% peat: 15% perlite), as well as 2 custom mixes, native mix (47% pine bark: 27% wood chips: 11% cypress dust: 10% sand: 7% peat), and garden mix (60% tree compost: 40% pine bark). Plants were grown for 15 wk, and measurements of visual quality, height, and dry masses were taken. Results indicated no significant differences in plant quality, height, or dry masses for wiregrass across all substrates. For lopsided Indiangrass, a significant height increase was observed in Pro-Mix HP compared to the native mix. Sugarcane plumegrass showed increased height in the garden mix compared to Pro-Mix 55BK and Pro-Mix HP. Despite the variation in substrate properties and the grasses’ natural community associations, growth performance was largely comparable. This finding suggests potential for using affordable, sustainable substrates in native plant production, reducing reliance on peat.