The largest flowering tobacco plant is Nicotiana sylvestris, and it has large lettuce green leaves that are shaped like those of the smoking type of tobacco.
Sometimes in a flower garden we have to remove the largest leaves at the base of these tall plants to avoid them shading out their smaller neighboring plants.
Though flowering tobacco is an annual, it is so good at self sowing that once you have one in your garden you will always have them in subsequent years.
The clusters of tubular white flowers hang down like slender bells, and they have a lovely fragrance especially in the evening.
These plants require almost no maintenance except an occasional watering during dry periods. Deadheading is not necessary, though it does spruce up these dramatic looking plants. There are many sizes of nicotianas ranging in height from 12 inches to 6 feet, but the smaller ones seems not to be as fragrant as the giants.
Plant them in full or part sun and they will persist into late fall.
Although the whites look pristine, there are also red, pink, salmon, and purple flowered nicotianas available, and the smaller varieities look best massed together, whereas the larger sylvestris makes a bold statement standing alone like a sentinel.
Wherever they self sow in my garden I leave them as they seem to have the knack of finding their own perfect spot.