This document is one entry in a series of questions and answers originally posted to the Purdue University Department of Horticulture & Landscape Architecture’s Plant Growth Facility Web site (http://www.hort.purdue.edu/hort/facilities/greenhouse/CornMethod.shtml) regarding best practices for corn plant growth in a greenhouse. Controlled studies were conducted with the goals of optimizing growth and yield; developing standardized methodology using readily available commercial materials; and providing recommendations for both high-tech and low-tech facilities. Digital images showing treatment differences are included, as well as statistical analysis of data. A summary of recommendations; materials and methods description; and a reference list are available in separate documents.