BORDERS 71 
Aside from shrubs, which are in a class by them- 
selves, perennials are the best for borders—for the 
simple reason that they do not have to be planted 
every year. Also they have a longer range of 
bloom that gives them an advantage over other 
herbaceous plants; and there is the widest variation 
of height, which is no small thing in the planning 
of effective borders. Very beautiful borders, how- 
ever, are made of biennials or annuals alone—or 
of various bedding plants, including not only the 
ordinary ones that are left to die in autumn but 
large and choice specimens of greenhouse plants 
that are kept under glass in winter. There is no 
rule save the very primitive one of doing as you 
please. 
"What is known as a hardy border is not neces- 
sarily one composed of herbaceous perennials ex- 
clusively. These may or may not be all; perhaps 
there are a few shrubs and more often than not 
there are annuals, biennials and bedding plants 
scattered through. But the very pillars are 
herbaceous perennials. 
No matter what class of plants is employed, it is 
a good plan never to use less than two kinds, these 
to be at their best at different times unless the pe- 
riod is a very protracted one. German iris backed 
by Michaelmas daisies is an example. Or, in an- 
nuals, Shirley poppies may be followed by China 
asters, letting an edging of sweet alyssum, which 
will outlive both, be regarded as the second flower. 
So few as three perennials will answer very well 
