The merits of Peonies are virtually endless! First, they are exceptionally hardy--easy to grow and carefree once established. One of the longest-lived perennials, a single plant can last for generations, blooming as reliably in its 50th year as it did in its 3rd!
Second, their phenol content makes them unappetizing to pests, including insects, rabbits, and even deer. Remarkably disease free as well, they literally need no attention once established.
Third, they truly offer three seasons of color. The new spring foliage is reddish; the bright blooms span late spring and early summer; and the fall foliage is often tinged with bronze or purple tones.
Fourth, they are equally suited for the landscape or the vase, offering old-fashioned cottage garden charm plus armloads of stunning blooms. Very long-lived in the vase, the flowers can even be upended and dried for use as everlastings (the singles are best for this). Mature plants have a pleasingly rounded, plump form, and the foliage stays fresh even in the dog days of August.
Fifth--but you already know this--the blooms are out-of-this-world lovely in color, fragrance, and form. As showy as roses and vastly easier to grow and care for, they are the unsung heroes of the flowering garden.
Peonies are a nice "bridge" plant in the garden, looking something like a perennial and something like a shrub. They have enough height to form a good backdrop to low-growing and petite annuals and perennials, yet are compact enough for a slender border or corner display. Planted in front of large shrubs or trees, they make a big splash of color without occupying a lot of space.
Traditional companions to Peonies are spring- and summer-flowering bulbs (because Peonies' lush foliage nicely hides the slumping stalks after the bulbs have bloomed), blue- and white-flowered perennials, larger flowering shrubs such as Azaleas and Rhododendrons, part-shade plants such as Epimedium and Helleborus, and ornamental grasses. (5 bareroot Peonies total)