Botany is a sub-field within biology dedicated to the study of all things related to plant life. You'll learn how plants grow and reproduce, master plant taxonomy and gain an understanding of common plant diseases. A degree in botany frequently serves as preparation for a graduate degree in the field, and can prepare you for careers in conservation, taxonomy or ecology. At some schools, a botany major might be called a major in plant science or plant biology.
Horticulture focuses on the commercial side of plant life, with a strong focus on mass cultivation of luxury plants such as flowers. You'll learn about plant growth and reproduction, as well as strategies for maximizing production, producing hybrids and marketing plant species. If you're interested in a career as a florist, grower or industrial seed producer, horticulture could be an ideal choice.
Agriculture, in contrast to horticulture, focuses on the practical application of plant growth, including growing plants as food. Some agriculture programs allow students to focus specifically on plant agriculture, while in other programs you'll get a generalized background in all forms of agriculture, including animal agriculture. You'll learn about plant diseases, best practices for plant cultivation, food chains and webs and best practices for maximizing cultivation.
If you're primarily interested in the aesthetic value of plants, a degree in a field that prepares you for landscaping could be the best choice. You might choose to major in landscape architecture, which will teach you how landscapes can balance architectural designs. If you want to landscape other people's yards, landscape planning could be a good choice that will help you understand how to balance plant colors and textures and ensure that plants remain alive and healthy.