Perennial Notes Excerpts


From time to time, we will be bringing you Perennial Search stories from our archives. This review of Algerian Iris first appeared in the Winter 1991 issue of Perennial Notes, Volume VI, No.1.

Algerian Iris: Iris unguicularis
By Sue Vrooman

from Perennial Notes Volume VI, No. 1 Winter 1991

Photo Credit: Thompson & Morgan Seed Co.

For dedicated gardeners in our area, the quest for elusive winter bloomers to brighten borders is often elevated to a passion. Nothing then is more satisfying horticulturally than finding a plant that not only blooms during this peaceful season, but is beautiful, fragrant, unusual, and easy to grow.

Iris unguicularis (I.cretensis; I.cretica; I stylosa) the Algerian Iris or Stylosa Iris, is such a plant. A native from Algeria and Greece east to Syria and Asia minor, it is a winter-blooming rhizomatous Iris. Its beauty is perhaps more welcome than its later and larger brethren, for it arrives while the garden is just beginning to dream of spring. Its blooms have been reported from late October until March in our area. Often, however, each clump flowers in a concentrated rush (February 8th to 28th for me in 1990).

The grassy evergreen leaves are 20 to 30 inches long and usually arched. Gertrude Jekyll called the foliage admirable, but some find it scraggly and untidy. While the variety 'Speciosa' throws blossoms well above the leaves, in many others the flowers the flowers are almost hidden; so some suggest cutting leafage back to four inches in the fall before buds develop to better display bloom. I have not found this necessary.

Algerian iris appreciate slightly-acid to alkaline soils, well-drained, but moisture-retentive and rather poor. Gertrude Jekyll encouraged a position protected from strong wind to prevent tattered flowers. Though a sunny Southwestern exposure is thought best, good luck here is possible in half shade - mine does well near an east wall - and light shade is recommended in hotter zones. Elizabeth Lawrence, famed Southern garden writer, reports a successful colony in Chapel Hill, NC under large oak trees. Algerian Iris is not a fussy plant and is the only winter-blooming species that Lawrence found permanent and dependable. It does resent disturbance, however, and take a while to settle into a new home. I have found it a rapid multiplier, mine increasing to 12-plus fans in two years; others have found it to be much slower. It is possible that some fans share roots and could not live if divided. Division is only necessary to relieve crowding and for propagation and is best done in early fall or after flowering, both times of active growth. Division at other times often results in death. Deep roots mate it a challenge to grow in containers.

The almost seamless solitary flowers are raised on 2: to 9" perianth tubes which look like stems. Mine stands about 5" high. The flower fascinates botanists by having its ovary at ground level with the flower held well above. The seeds develop hidden here at the leaf base, protected from the cold. According to Edith Eddleman, the NC State Arboretum (ed. note: now J.C. Raulston Arboretum) has raised Algerian Iris from seed to bloom size in two years. Grower Colin Rigby says it takes four years in his zone-9 garden. He finds seed is not set easily, possible due to poor pollination, and has had partial success with hand pollination. The flower, 3" to 4" across, is immediately recognizable as an iris. Christopher Lloyd calls its color the quintessence of mauve, "Bright, but delicate and much enhanced by the fragile texture and elegant poise of the flower." Its center is white, dashed with violet-purple and sports a central golden yellow signal or patch on the falls. Although there are a number of hybrids of cultivars, Colin Rigby of Portable Acres is the only source that carries any. All are said to be desirable, though some, notably a white form, are slow multipliers. Mr. Rigby recommends 'Angustifolia', a fast multiplier and heavy flowerer, and 'Mary Barnard' with short 12" to 14" foliage, lush green leaves. Nice clumping habit and dark flowers with wider petals. To add to their indisputable charm, the flowers of Algerian Iris are fragrant. E.A. Bowles maintained that the first real breath of spring arrived with a whiff of this iris. One may gather flowers while still in bud by pulling, rather than picking. Gentleness is required since the flower shares a short stem with two smaller buds. Individual flowers are short-lived, each lasting only a few days. Algerian Iris is hardy throughout most of the South (zone 7-10). Its only serious pest is the slug.

I challenge growers to get this fine plant into production. I know of only three sources for it in this country - and I really had to dig to find those. Every winter garden deserves an Algerian Iris tucked in to delight winter ramblers and lure gardeners from the fireside.

(Ed. Note: Sue's challenge was answered as these lovely Iris are more widely available now.)