Summed up in a single phrase, a perennial is a plant that lives and flowers for a number of years leaving behind no woody structure each season. Examples of perennials would be Campanulas, Delphiniums, Heleniums, Hellebores and Rudbeckias. So, if you plant perennials you can expect a reliable splash of colour year on year which will only get better as the plants grow in size.

It might be helpful to contrast perennials with some other groups. I’ve not been too technical as in horticulture many of these terms are used quite loosely.

This is not a form of biology, but reference to how tolerant of our winters. Perennials can be either hardy (which we grow),  half hardy (in need of some protection over winter) or tender (will die if exposed to the cold).