he number of distance education courses available in American higher education has increased substantially over the past decade. The number of higher education students enrolled in an online course during the fall 2005 term was close to 17% of the total population of 17 million students (Allen and Seaman, 2006). The objective of this research was to develop and evaluate a one credit introductory horticulture course delivered exclusively online. This course has five modules covering the basic horticul- ture topics of: plant identification and characteris- tics; plant growth and development; the rooting environment; selecting plants for the landscape; and putting plants in the landscape. Eleven graduate students (37.9%), nine undergraduate seniors (31.0%) and nine adult learners (31.0%) have com- pleted the course since fall 2006. Evaluations revealed an overall course rating of 3.90 (scale: 1=poor; 5= excellent). When asked what aspects contributed most to their learning, three themes were prevalent: the assignments (40.5%), the lectures (27.0%) and the asynchronous environment (10.8%). When asked what distracted from their learning four themes were evident: difficulty of the assignments and format (17.5%), wanting more in the lectures (15.0%), technical problems (15.0%) and problems with assignment feedback and grading (10.0%).