Bearded iris or Iris germanica is a stunning member of the iris genus which is famous for the distinctive furry “beards” which stripe its petals. This plant is popular for borders in the garden, and it requires minimal maintenance, an ideal trait in the eyes of some gardeners. Many garden stores sell iris starts which can be planted, and gardeners can also request rhizomes from friends and neighbors who cultivate bearded iris in their gardens.
This plant has six petals, three of which point up, and three of which point down. The downward pointing petals or “falls” have the beards, which can vary from dense furry stripes to fine wisps of hair. Bearded iris come in a rainbow of colors, with many blooms being bi-colored. The blade-like leaves classically grow in an array which resembles a fan. Depending on the cultivar, the iris can bloom between April and June, with some cultivars blooming again in the fall. The height of the plant also varies, from the self-explanatory “tall iris” to the mini-dwarf iris, which is about the height of a hand.
Although the bearded iris is sometimes taken to be a bulb, it actually propagates with rhizomes, thick fleshy roots which eventually develop knobbly outgrowths which turn into new plants. Growing rhizomes can be tricky, as they require some special care. The roots which dangle from the rhizomes like to be moist, while the rhizomes themselves need to be kept relatively dry or they will be subject to rot.
It is best to plant bearded iris in the late summer and early fall, to allow them to grow accustomed before the winter. To plant this flower, a mound of soil should be created in a deep hole, and the divided rhizomes should be carefully positioned over the soil, allowing the roots to cascade down the side of the mound. Then, the hole can be filled, partially covering the rhizome. Bearded iris should be planted in a sunny spot, and the mound of soil should be dense so that it will hold moisture, while light, loamy soil should be mounded over the rhizome.
Bearded iris will grow in USDA zones three through nine. Every three to six years, they need to be divided and checked for rot around six weeks after they bloom. To divide, the rhizomes are dug up, washed, and trimmed to remove any soft or rotted sections. Then, the foliage should be trimmed back to around hand height, and the rhizomes should be cut apart so that each fan of foliage is on a separate piece. These pieces can be planted as directed above. Fertilizer should only be applied if the foliage seems dull after the blooming season.
Good companion plants for this iris include lilies, roses, peonies, and coneflowers.