Technically, a perennial is a plant
that lives more than 2 years but there is a wide range
of how long individual species ultimately live.
This is
true of all forms of plant life from trees to shrubs to
herbaceous perennials to bulbs. We all know of ancient
oak trees that have been around for a century or two
while some ornamental cherry trees may live only a few
decades. Peonies and hostas are noted for having lives
that may mirror that of the human span while herbaceous
perennials such as
delphiniums, certain
coreopsis and
some primroses may only live a handful of years.
Again, the key is to get to know your plants. It does
not mean that you automatically avoid short-lived
perennials. Rather, if you use them, be aware that you
will probably have to replace them periodically.
