Copper Hydroxide Controls Root Distribution In Container-Grown Carpentaria Palm
The influence of copper hydroxide [Cu(OH)2] application to interior container surfaces on root growth at the container-medium interface was studied using Carpentaria palm [Carpentaria acuminata (H. Wendl. & Drude) Becc.]. Cu(OH)2 (0, 100, 200, or 400 g) was mixed with one liter of either white latex house paint, or NuFilm-17 surfactant, and applied to all surfaces inside 0.5 liter containers. Plants were grown in untreated containers, in containers treated with paint or NuFilm-17 only, or in containers treated with Cu(OH)2 in paint (100 g rate only) or NuFilm-17 (100, 200 or 400 g per liter). When applied in paint or NuFilm-17, Cu(OH)2 reduced root growth at the container-medium interface, controlling the circular growth pattern commonly observed in container-grown plants. Controlling circling root growth at the soil-container interface did not influence shoot or root dry weight, but did reduce total root length. Application of Cu(OH)2 with paint was unsightly, while application with NuFilm-17 was almost unnoticeable.