This page defines the terms that I use to describe the size of plants. I refer to them in the Plant Database, as well as other places such as articles, videos, and social media.
There are no official, scientific terms for plant size groupings. These are my own personal definitions; other websites and people may refer to plant sizes differently.
In many cases, plant sizes are subjective. Judgment can be affected by growth habit, plant form, comparative scale of plant parts, and so on. For example, a vine or trailing plant might grow to be several feet long, but if the leaves are only 1/2 inch long, I’d still consider it a miniature plant.