A perennial is a plant that endures more than two growing seasons. Generally, they herbaceous (non-woody) plants that die to the ground each fall and regrow the following spring from the same root system. The term "perennial" refers only to the plant's normal life cycle and does not imply that a plant is cold hardy nor it imply that the plant will die back in the winter. Some plants that are perennial in a mild climate may be annuals in colder ones and plants considered perennial because they resprout from the ground may in fact be evergreen shrubs or trees in a climate where they don't freeze. This makes the classification of a plant as perennial difficult as it really depends where one gardens and how the plant it is treated. Further compounding this is the tendency for gardeners to lump plants of similar usage together within the classification "perennial". Using this criteria a plant is a "perennial" because it is a suitable choice for the perennial garden. Often included in this broad perennial category are true perennials, shrubs and sub-shrubs (plants with woody bases and herbaceous tops), vines, bulbs, ferns and ornamental grasses.
The size of a perennial can range from a few inches, which would be a very low, creeping groundcover, to several feet tall and wide. Some very large shrubs, such a Melianthus major, can be forced to act like a perennial by annually cutting back to ground level, or stooling the plant.
It is best to plant perennials in spring and fall, except in extremely cold areas, where they should be planted at the end of summer to allow them time to become firmly rooted. We have information pages on the following plants that are perennials or have traits that are lend their use in the perennial garden. Many are included in other classifications, such a Lavenders in shrubs, as well. Also Search our database for all the Perennials that we grow.