Although gardeners fret and fuss a great deal about having the right kind of fungi in their soil, we will focus our discussion on the plant kingdom, also called Plantae in botanical Latin. The plant kingdom is divided into subcategories, as shown below. Kingdom Division Class Order Family Genus Species Variety or subspecies Cultivar Forma For most gardening enthusiasts the categories of division, class, and order are not significant. However, things get really interesting for us at the family level. Just like people within the same family share characteristics, so do plants that belong to the same family.
All family names end in the letters 'aceae' and begin with a capital letter.
For example, plants in the Rosaceae family typically have flowers with five petals, or petals arranged in groups of five. The Rosaceae family is one of the largest plant families. Another family is Ginkgoaceae. It is one of the smallest plant families. The famous ginko tree, botanically called Ginkgo biloba, is its' only member.