Perennial means, plants that come back on their own every year, without the need of spreading seeds or planting bulbs. These plants grow by their base root system. This means, if you disturb the original plants base root system (which includes the trunk), the plant may not come back at all. If you remove it, it will not come back. It is written that most perinnials only last 3-4 years. Some do, some dont. Some plants are soo sensitive that if you cut back any of the plant in the fall, the entire plant may die.
Annual means, needing to be planted each year either by way of purchase or allowing the plant from the season before to spread its own seeds/bulbs. At season end, the remaining plant can be removed. This info is very misleading. All perennials come back from year to year, and 'some' annuals DO come back by themselves..... not all annuals do. Garden shops will tell you annuals do not come back each year. Dont believe it! Once you find out which plants will come back on their own, they are nice to choose.
I have listed some perinnials and come annuals but all of these come back each year with very little effort!
