The Saddleback College Horticulture as well as Landscape Design Programs were established in 1975, and currently offer horticulture or landscape design certificates and associate of arts or science degrees. Both programs offer a wide range of comprehensive courses to students interested in obtaining occupational skills for employment in the industry, for upgrading current occupational skills, or for fulfilling transferability requirements to a four-year institution.

Within the Horticulture and Landscape Design Program, Dr. Johnson joined the Technology and Applied Sciences and the Mathematics and Science Divisions in 1974 as an associate professor of biology and horticulture.  In addition to General Horticulture (Hort 20), General Biology (Bio 20), he also teaches in Plant Materials – Trees and Shrubs (Hort 11), Ornamental Native Plants (Hort 29), Plant Propagation (Hort 112), History of Landscape Design (Hort 115), as well as well-liked field study courses (Hort 160 to Hort 165) and special topic courses (Hort 189) in tropical plants; orchids and bromeliads; herbs and vegetables, roses and in other related topics concerning propagation, use, and care of plants.  With the increased demand and popularity of the Internet courses, Dr. Johnson has also developed online versions of his lecture courses: Plant Material – Trees and Shrubs (Hort 11), Plant Material - Herbaceous Plants (Hort 10), Plant Propagation (Hort 112), and History of Landscape Design (Hort 115).