Vol 117 (2004): Proceedings of the Florida State Horticultural Society
Ornamental, Garden & Landscape

Response of Rumohra adiantiformis to a combination of calcium, urea, magnesium and boron

Dana M. Venrick
University of Florida
Published December 1, 2004
  • rumohra adiantiformis,
  • leatherleaf fern,
  • calcium nitrate,
  • urea,
  • magnesium sulfate,
  • boron,
  • boric acid,
  • calcium,
  • nitrogen supplement,
  • magnesium supplement,
  • calcium supplement,
  • boron supplement
  • ...More


An experiment was conducted using leatherleaf fern (Rumohra adiantiformis) to evaluate production benefits of a commercially available product containing urea, calcium nitrate, magnesium sulfate and boric acid. Two adjacent plots, owned by the same growers, were selected that use the same water source and have been maintained by the same University of Florida, Institute of Food and Agricultural Sciences (IFAS) recommended practices for the past five years. The test plot received, in addition to standard inputs, ten oz per acre per week of the test material for nine weeks. The control site received only standard inputs. Fronds with stems and frond tissue samples were collected before, during and after the study. Average stem size, measured just below the first "leaf", increased by 148.2% in the test plot vs. a 36.7% increase in control site stem size. Average frond weight increased by 115.8% in the test site while frond weight in the control site increased by 41.9%. Tissue analysis demonstrated a 74.4% increase in calcium (Ca) in test site tissue vs. a 15.6% increase in Ca in tissue from the control site. Magnesium (Mg) in tissue from the test plot increased 11.3% vs. a 52.6% increase in control site tissue. Boron (B) increased 38.7% in tissue from the test plot vs. a 27.9% increase in the control site tissue. Visually, the foliage in the test plot was a darker green color than foliage from the control site. Visually, the test plot ferns had fewer symptoms of disease than ferns in the control site. The use of nutritional supplements, such as the one used in the study, may open an opportunity for leatherleaf fern growers to increase production and improve sales with fern that has a more appealing appearance.