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The School of Horticulture & Agribusiness is the best option available for a someone interested in learning horticulture. Their training strategy allows students to earn money while they learn and combines supervised, structured, on-the-job training with theoretical related instruction. The program is designed for the student requiring a core training in ornamental horticulture. Emphasis is placed on greenhouse management, nursery production, grounds maintenance and landscape planning. Students receive both, an accredited post-secondary diploma and completion of their apprenticeship in-school training.

Here is a link that might be useful: School of Horticulture