1. Defining leaves.
Most of us recognize a plant by its flower, but in horticulture school students are taught to identify plants by all their characteristics, and leaves are among the most complex. Foliage shape, arrangement, venation, margin, tip and surface are all classified. The great thing about getting to know all the terminology—aside from making you a sparkling conversationalist—is that you can imagine what the foliage looks like from the description in a catalogue without pictures.