Solomon’s Seal – 2013 Perennial Plant of the Year

Posted: March 7, 2013

One of the pleasures of early spring, for a gardener weary of winter, is watching herbaceous perennials emerge from the bare ground, with lengthening stems and unfurling leaves often changing color as they develop into the full-grown plants that will add color, form, and texture to the garden during the growing season.
Solomon's Seal Emerging

Solomon's Seal Emerging

Of such interest is variegated Solomon’s Seal, Polygonatum odoratum ‘Variegatum’, which also happens to be the Perennial Plant of the Year for 2013. Selected by the members of the Perennial Plant Association, an organization of perennial plant growers, sellers, educators, and gardeners, the Plant of the Year is generally not a new introduction, but a time-tested plant that has proven itself to be hardy, adaptable, low maintenance, generally pest free and disease resistant, and that provides more than one season of ornamental interest in the garden.
These sound like ideal plants for any perennial gardener! The first perennial selected, Phlox stolonifera, in 1990, has been followed in the years since by equally outstanding choices. If you are wondering, out of the bewildering array of herbaceous perennials available at garden centers, which to choose for your garden, the Perennial Plant of the Year list is a good place to start. The complete list is available at the Perennial Plant Association’s website
Back to variegated Solomon’s Seal: this variety is a non-native herbaceous perennial, best suited to part or full shade, whose elegant beauty belies its tough constitution. And it’s a good example of the seasonal color changes exhibited in many perennials.
In early spring, the newly emerging stems are blushed pinkish red, which slowly fades to the green of summer as the stems lengthen. In fall, the green and white foliage turns a soft buttery yellow before the stems topple after several frosts.
Solomon’s Seal is grown primarily for its attractive foliage and architectural form. The soft green lance-shaped leaves, streaked and edged in creamy white, are borne on 2 to 3-foot tall unbranched stems that arch gracefully to form an impressive linear presence amongst companion perennials such as hostas, gingers, heucheras, epimediums, astilbes, ferns, brunnera, pulmonaria, and hellebores.
If foliage and form were not enough, Solomon’s Seal also has pretty flowers. From spring through early summer, dangling pairs of small, white, bell-shaped flowers hang from the leaf axils along the arching stems, accentuating the linear form of the plant. The flowers carry a light but sweet fragrance, most noticeable in evening, and are sometimes followed in fall by dark blue fruits. Stems, whether with flower or foliage, make good cuts for flower arrangements.
Although it prefers consistently moist soils high in organic matter, once established, it is durable enough even for that toughest of shade conditions, dry soil amongst tree roots, although it won’t be as impressive as in richer soils. It is long-lived and spreads slowly by rhizomes, thumb-sized jointed stems just below ground level, from which the stems arise each spring. The circular stem scars on the rhizome are supposedly the source of this plant’s common name, Solomon’s Seal. In good growing conditions, this plant can gradually spread to form an impressive groundcover for the shady garden.
And although Solomon’s Seal is pest and disease resistant for the most part, as befitting a Perennial Plant of the Year, there is one pest not usually mentioned in the literature that can occasionally decimate the foliage: the larvae of the Solomon’s Seal Sawfly.
The female adult sawflies (an insect related to bees and wasps) cut slits and lay eggs in the leaf stalks of Solomon’s Seal. The larvae, which look like little worms, appear in late spring to early summer, feeding en masse on the undersides of the foliage. They leave elongated holes between the leaf veins, as well as consuming leaf edges, and can reduce a mature plant to nothing more than stems in just a few days. The larvae can feed for about four weeks; then drop to the soil to pupate, where they remain until the following spring, when the cycle begins again.
Early scouting is helpful to detect the larvae before they do too much damage; if you do notice them, hand picking is one option for control; or a less toxic spray such as insecticidal soap can be used on the larvae. Fortunately, there is only one generation per year, so good control one year can substantially reduce the problem in succeeding years. But this minor pest should not be enough to deter you from adding Solomon’s Seal to your shade garden, since this beautiful plant exemplifies so many attributes worthy of a Perennial Plant of the Year.