Improvement of Rhododendron and Forsythia Growth with Buffered-Phosphorus Fertilizer
Rhododendron and forsythia plants were grown in a soilless medium containing one of four phosphorus treatments: soluble P, slow-release P, or 0.5% or 1% solid-phase alumina-buffered P (Al-P). Soluble phosphorus concentrations in the leachate were highest for soluble-P treatment and lowest for the Al-P treatments. Al-P supplied adequate P for plant growth throughout the season while substantially reducing P leaching. Forsythia plants produced more shoot dry mass when grown with 0.5% Al-P than with the other treatments, and larger rhododendron plants were produced when fertilized with 1% Al-P.Abstract
Contributor Notes
The authors thank the Pennsylvania Department of Agriculture and The Horticultural Research Institute, 1250 I Street, N.W., Suite 500, Washington, DC 20005, for support of this project.
2Professor of Postharvest Physiology, Graduate Student, Professor of Ornamental Horticulture, Associate Professor of Ornamental Horticulture, and Associate Professor of Plant Nutrition, respectively.