Panicum

Botanical/Latin
   Panicum

Pronunciation
   pah-ni-kum

Common Name
   Switch Grass

Hardiness zone range
   4 - 9

General Comments
Superb, easy to grow grasses that form narrow, upright clumps of delicate, grayish-green or silvery-blue foliage, with graceful, airy, cloud-like, flower panicles appearing above the clumps in late summer and fall. As the season progresses from summer into autumn, the flowers and foliage gradually change color, taking on shades of yellow, bronze, and burgundy red, eventually leading to beige as winter approaches.

Uses
The narrow, upright habit and airy, "see through" flower stems are perfect for using as accent plants in beds and borders, or among low carpeting, ground covering plants to break up and relieve flat lines. In small sites, where space is at a premium, they can be used as individuals or in small, informal groups, where the distinctive habit is both dramatic and colorful. Once they become established, they are remarkably tolerant of wind, drought, and even salt spray, so they are useful in beds near the seashore, roads, and larger exposed places like sloping banks, raised beds, or even roof gardens. They persist well into winter, and help to extend the seasonal interest at a time of year when most other plants are not visible. The cultivars we offer are selections from native species, so they are perfect for meadow and natural style gardens, and the seed heads attract and provide food for small birds. They can be used as container plants, and the gracefully intricate flower panicles make excellent cut flowers which can be used fresh or dried.

Light Preference
Sun with some tolerance to light shade

Culture
They are tough, hardy plants that require only minimal care and attention; all they need is a reasonably fertile soil that is well drained. They can tolerate fairly dry conditions, so free draining soils that have been supplemented with some extra humus (peat, garden compost, etc.) are ideal. They are not troubled by any serious pest or diseases, and require very little maintenance, except to tidy up the clumps by trimming back the remaining old foliage in early spring. They will happily grow and prosper in soils that are low in nutrition, but respond handsomely if given occasional light dressings with a well balanced fertilizer. Older clumps should be lifted and divided about every three years; the best time to do this is either in autumn or early spring. They are easy to pull apart and replant; it helps to keep them vigorous and encourages plenty of colorful new growth.

Background
Panicum is the Latin name for millet. Only a few of the hundreds of species are ornamental enough to have garden merit, and of these Panicum virgatum is the most colorful and important. It is an American species that is found over an immense area from southern Canada to Florida and westwards to the Rockies and even extending south into Central America. The word virgatum, means wand-like, which refers to the flimsy, sometimes floppy habit that gave it the common name Switch Grass. It was introduced to cultivation in 1781, and several forms with good autumn coloring were selected in Germany, where the cultivation of grasses is very popular. Much more recently, American gardeners and nursery people have selected some splendid forms with distinct, blue shaded, summer foliage. The best known one is Panicum virgatum `Cloud Nine'. It was selected and introduced by Bluemount Nursery in Maryland, and is, in our view, the best and most reliable form, standing a full 6 foot or more with strong, vertical, blue foliage, and airy plumes that turn reddish tones in autumn. Our other favorite is Panicum virgatum `Prairie Sky'. It is shorter in stature and a lighter shade of metallic blue. It was found by Roger Gettig (from Holden Arboretum in Ohio) growing along a railroad track in Wisconsin.

Splendor Suggestions
The seed heads provide winter interest and food for small birds, but can lead to a proliferation of little seedlings appearing each spring. To prevent this, consider removing the seed heads in fall, or apply a deep mulch around the clumps each spring.

Companion Plants
The striking blue foliage and erect habit go beautifully with most plants, so finding compatible partners is not difficult. One approach might be to plant them with other native perennials. Asters, Boltonias, Gaillardias, Coreopsis, Echinacea, Solidago, and Rudbeckias are just some of the possibilities. Another consideration would be to pick out the blue foliage and fall coloring with Sedum `Autumn Joy', Stokesias, Nipponicanthemum, or some of the magnificent Japanese Anemones.