2025/07/08 by Carla C. Caballero Mejia, Mark H. Brand, Jessica D. Lubell-Brand · 1 voice · 1 citation
Agricultural and Biological Sciences · #Botanical Research and Applications #Botany and Plant Ecology Studies #Botany, Ecology, and Taxonomy Studies
paper · doi:10.21273/hortsci18562-25
openalex publication_date 2025/07/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/26
Hemp ( Cannabis sativa ) hurd fiber was studied as a potential new substrate to substitute for sphagnum peatmoss in container production of petunia ( Petunia × hybrida Shock Wave ® Coral Crush) and geranium ( Pelargonium × hortorum Maverick™ Red Hybrid). Media composed of varying proportions of hurd, peat, and vermiculite at 1:0:1, 0.33:0.66:1, 0.66:0.33:1, and 0:1:1 (control) were evaluated. Petunia grown in 0.33:0.66:1 medium had similar shoot weight, flowers, and plant width and were visually indistinguishable from plants grown in control medium. However, as the amount of hurd substituted for peat increased, plant performance declined. Geranium grown in 0.33:0.66:1 medium had greater shoot weight and width than plants in control and 1:0:1 media. Media pH registered above and below recommended ranges for petunia and geranium, respectively, based on pour-thru testing. This may have led to growth reductions due to Fe deficiency for petunia in 1:0:1 medium and Mn toxicity for geranium in control and 0.33:0.66:1 media. Growth of petunia and geranium in peat:vermiculite medium with either hurd or wood fiber in substitution of peat at 50% was also studied. Petunia in the hurd medium were slightly smaller than those in wood fiber and control media, whereas geranium was similar across media. This is the first reported use of hurd as a substrate for bedding plant production. These findings suggest that hurd is a promising new substrate and may be substituted for ∼30% of the peat portion of a standard peat:vermiculite medium to produce high-quality plants.