Protective cultivation is essential for many cycad species. But what are the safest and best methods for growing robust cycad seedlings? A new project led by Vickie Murphy, MBC Nursery Curator, sought to maximize survival and growth of young cycads.

Although many soils are used by nurseries, the rarity and value of cycads prohibits many growers from experimentation with these treasured seedlings. A recent surplus of garden-cultivated Zamia pumila seed, provided by colleagues at Jardín Botánico Nacional Dr. Rafael Ma. Moscoso, allowed for rigorous scientific evaluation of media effects on cycads.

The experiment evaluated nine different media types with rigorous controls and statistics, from traditional organic mixes to more technical media such as fired clay. The results suggest that silica sand promotes the most robust growth and health of Zamia seedlings, and careful statistical evaluation suggests the air space provided by this medium was helpful.

Vickie performed this study as part of her Masters Thesis in Horticulture at the University of Florida. In addition to Vickie’s new academic findings, the science is directly relevant to Montgomery’s work. Vickie highlights how the efficiency gains help:

Greenhouse space is much like real estate: every square foot counts! Increasing the growth rate of cycads in the nursery reduces the number of years it takes to get them planted out in the garden. This opens up more space to conserve new plants.

The research is featured on the cover of the latest issue of HortScience, published by the American Society for Horticultural Science.