A favorite for generations of gardeners, cannas make gardens come alive with their exotic flair, tropical hues and showy flowers. Because they can handle the heat and can grow up to 6 ft. tall, they've long been treasured for filling large gardens, public parks and spaces. These tender plants are also available in dwarf sizes that are suitable for containers. Deer tend to pass them by. Cannas are available in an array of foliage colors and flower colors. They grow best in well-drained soil rich in organic matter. When buying cannas for sale online, take into consideration their mature height and spread. Also consider their flower and foliage color.