Iris is such a vast genera that offers a species for just about every situation in the garden. Their flowers are quite elegant, and have inspired many artists through the world to feature them in their masterpieces. This elegance can also inspire the gardener to incorporate them into the living masterpiece of the yard!
Their foliage lends a strong vertical feel with their pointed blades. This can be a great structural and textural contrast with perennials and shrubs. They look great in the garden as a lone seasonal focal point or planted in swaths.
This article focuses on non-bulbous bearded, Japanese and Siberian iris, and a few other jewels in the genus. Bearded Iris (Iris germanica) are quite tough and can grow in some of the most neglected spots.
My favorite collection of bearded Iris grew in my west facing parking strip with no additional water. They have huge flowers that come in every color of the rainbow and then some. Each flower has a fuzzy strip (the beard) that is on the lower petals and large ruffled upper and lower petals.
Iris come in a range of colors from white and yellow to blue red and brown. Bloom time varies with microclimate. Generally it is end of April through the beginning of June. Portland Nursery has a selection of bearded Iris this time of year in some of the more common colors. Bare root are available in the fall bulbs. In August, the Iris Society has a sale at our Stark location with almost every color of bearded Iris imaginable.
Iris palladia 'Auro Variegata'
Japanese Iris (Iris ensata) have large flattened blooms in late spring to early summer. Flower color varies from shades of purple and blue to pink and white. Japanese Iris have a distinctive yellow signal on the lower petals.
Some varieties have exquisite contrasting veining. Most Japanese Iris grow about 3' tall. They prefer moist soil (they do not tolerate drought). They are great in shallow water on the edges of ponds or in rain gardens.
Iris pseudoacorus is another vigorous species for ponds or try Iris ensata 'Auro Variegata' for a jazzy foliage addition.
Siberian Iris (Iris siberica) have slender foliage and sleek crisp flowers. They bloom May thru June in colors of white, blue and purple. The slender foliage adds a wonderful vertical and textural accent to the garden. Siberian Iris are one of the most popular beardless varieties and are quite easy to grow.
Some favorite varieties include 'Caesar's Brother' (a rich purple), 'Lavender Bounty' (clear lavender pink) and 'Sparkling Rose' (lilac rose color).
Iris pallida offers some striking foliage colors to the genus. We carry Iris pallida 'Albo Variegata' (white and green) and 'Aureo Variegata' (yellow and green) which are absolutely stunning spring through fall. In the fall the foliage of Siberian and Japanese Iris turn gold.
Siberian Iris often yield interesting seed pods as well. Irises are great plants for the beginning or experienced gardener. Try them out and enjoy the beauty that has inspired creative minds for years.
Common name: Iris
Origin: Over 300 species native to temperate areas of the northern hemisphere.
Culture: Conditions vary greatly among species. Generally Iris thrive in full to part sun. Some species are more shade tolerant. All Iris thrive in well drained soil. Bog species (I. cristata, I. pseudacorus, I. sibirica) can grow in full sun and permanently damp soils.
Most Irises prefer regular water during the growing season, and little to no water when dormant. There is also bulbous Iris such as the Dutch Iris which bloom in March (plant bulbs in fall.)
Pests and Diseases: Irises can be food for slugs and cutworms (as are most plants.) Non-bog species are prone to rot if they are perpetually soggy. Bearded irises may not bloom if the rhizomes are not on top of the soil or if they are over crowded. The most common disease tends to be leaf spot.
Maintenance: Siberian and Japanese iris require little to no maintenance. Bearded Iris benefit from dead heading of individual flowers and a leaf trim in summer. In fall, cut back and clean up old foliage to keep tidy and help prevent leaf spot.
Propagation: Divide bearded iris in late summer after flowering. Siberian and Japanese iris can be divided in late summer and fall. Some species can grow from seed planted in fall.