Garden favourites for more than a hundred years, these statuesque beauties still capture our hearts.
TOGETHER WITH LILACS AND PEONIES, BEARDED IRISES have long been considered an old-fashioned garden staple, so much so that even non-gardeners can put a name to them, and iris-smitten artists from Monet to Van Gogh have filled their canvases with these uniquely formed flowers (vertical standards with drooping falls) and their rich stained-glass hues. But modern bearded irises have come a long way since the late 19th century, when those artists were immortalizing them in paint: Today’s cultivars are available in virtually every colour except scarletred and true blue. Some varieties sport solid colours (known as “selfs”) while others are a kaleidoscope of contrasting hues, and the beards for which these plants are named are now larger and more colourful. Many varieties are fragrant, some
˚ even rebloom, and all modern cultivars have thicker, sturdier petals than their wild counterparts. The bearded irises we grow today are principally derived from just two species: the blue-flowered Croatian orris root (Iris pallida) and the yellow and white Hungarian iris (I. variegata) with its intricate venation. Where these two species meet in the wild, they produce a natural hybrid which was formerly classified as a true species (I. germanica), hence the alternate common name, German irises. Bearded irises have been grown in European gardens since the 15th century, and gradually gardeners began selecting flowers with unusual patterns and colour combinations. In 1822, the first hybrid bearded iris (named ‘Buriensis’) was introduced in Paris. For the next 60 years, hundreds of French cultivars were raised from open (insect-pollinated)
crosses. Needless to say, these fetching French flowers soon attracted the interest of English gardeners, and the single biggest breakthrough in iris breeding took place in English physiologist Sir Michael Foster’s (1836-1907) back garden.
In the 1870s, Foster began crossing common bearded irises with four newly discovered species. Unlike I. pallida and I. variegata, which are both diploid (each having 24 chromosomes), these new species were natural tetraploids with 48 chromosomes. When diploids and tetraploids are crossed, they usually produce sterile (or “mule”) flowers, resulting in a breeding dead end – but, miraculously, Sir Michael’s crosses produced fertile tetraploids with bigger flowers, thicker petals and highly saturated colours (much like tetraploid daylilies).
Now the game was afoot, and Sir Michael quickly released six cultivars which are the ancestors of most of our modern varieties. While studying at Oxford, William Rickatson Dykes (1877-1925) met Sir Michael, caught the iris bug, introduced new varieties, penned the first comprehensive Iris monograph in 1913 and, ultimately, lent his name to the Dykes Medal, still the highest award for new iris cultivars.
By 1925, iris hybridizing had become a serious business in North America, especially in Oregon. In this region, breeders collaborated openly, generously sharing their knowledge toward the common goal of producing improved bearded iris cultivars. Research into developing reblooming bearded irises was pioneered in the 1970s by Dr. Lloyd Zurbrigg, and while rebloomers are still a relatively recent phenomenon, breeding is ongoing, and twice-blooming irises may soon become the norm for these majestic flowers.
in nature, iris “beards” act as pollen guides to steer foraging bees in the right direction, but in the absence of insects, they also help to trap pollen, enabling the selffertilization of individual flowers. ‘raspberry blush’ intermediate bearded iris
‘NAPLES’ TALL BEARDED IRIS ‘BLUE SUEDE SHOES’ TALL BEARDED IRIS
‘IMMORTALITY’ TALL BEARDED