Dotting the grounds of Marin Art & Garden Center, and perhaps the hillsides around you as well are splashes of bright purple, the blooms of Douglas Iris. This native plant grows wild all along the California coast, and it thrives in the dappled shade under MAGC’s English oak as well as on grassy slopes around Marin.
The name Iris is taken from Greek mythology and means “rainbow.” You can certainly find iris that bloom in a wide range of colors, from pure white to darkest purple, with pinks, yellows and blues in between. There are so many beautiful varieties of iris, you can create thrilling displays of flowers by selecting a range of colors and heights. Flower types can be bearded, with cascading petals that have a furry “beard” running down the center, or beardless, like the Douglas iris, which feature colorful veining but no fuzz.
If you wander around Marin Art & Garden Center at this time of year you’ll see iris all over; some native, some cultivated, and some naturally occurring hybrids. A light counterpoint to the Douglas iris is the “long-tubed iris,” which features just a light purple flush on its petals. These native iris are mostly volunteers, but we have also planted garden varieties around the grounds. Look for the Iris germanica, a classic bearded type, Iris japonica, a delicate beardless iris, Siberian iris and Iris tuberosa.
While in many parts of the world it’s important to wait until the fall to plant iris, here in the Bay Area, we are fortunate to be able to plant them more or less year-round. You may want to do your shopping in the autumn, though, when suppliers have the best selection. Our partner, Brent & Becky’s Bulbs, offer iris of all types, and if you make a purchase through our link, their generous Bloomin’ Bucks program supports Marin Art & Garden Center!
Iris either grow from bulbs, or through rhizomes, structurally part of the plant’s stem that remains under the soil. The ginger we use for cooking is the rhizome of that plant, and iris rhizomes look similar, with knobs and nodes that spread horizontally underground. The plant can send shoots upward from these nodes, so iris tends to grow in clumps that all extend from the same rhizome.
Autumn is the best time to divide existing iris plants by digging the rhizomes out of the soil in a clump. Look for smaller, young offshoots to replant, as these will be most likely to bloom. Cut back the leaves to about 5 inches high and replant the rhizome with the leaves up, and the rhizome just covered by earth. You’ll want to leave a good radius around the new plant, at least a foot or so since they’ll continue to spread under the soil. Often, rhizome type iris will bloom not long after planting, so you may get flowers at unusual times of year. Regardless, cut back the flower stalks to their base once the flowers have withered, and you’ll encourage more blooms to come.