The 2012 ASHS Annual Conference

Cycads comprise the most threatened group of plants on earth. Appropriate container media conditions are crucial to successful cultivation of most cycads. At Montgomery Botanical Center inorganic media have improved survival and growth of several very rare and horticulturally challenged Zamia species. Zamia pumila seedlings germinated at MBC were selected at random and transplanted into one gallon containers. The following substrates were evaluated: (1) Greens Grade Profile (2) Turface  MVP (3) 50% silica sand / 50% profile (4) Axis (5) Permatil (6)  Perlite (7) fine Pumice (8) silica sand and (9) Fafard Potting Mix #2. Plants were top dressed with 30 grams per pot of Nutricote Total fertilizer, 18 N – 6 P₂O₅  - 8 K₂O. Seedlings were transplanted on October 1, 2010 and grown for one year.  Media physical properties, leaf growth parameters and nutrient status were measured at the beginning and end of experiment. Sand produced significantly higher leaflet counts than all other substrates. The second highest leaflet counts were on plants grown in the Fafard #2, perlite, and pumice. The poorest performing substrates were Turface, Profile, calcined shale, and diatomaceous earth.