The only thing better than an iris in bloom is an iris that blooms more than once.
by Marie Hofer, Gardening editor, HGTV.com
As stunningly beautiful as irises are when they're in bloom, they can be pretty uninteresting for the rest of the year. So imagine the wonder of having an iris reblooming in the same season--sometimes once more, sometimes twice, and depending on variety and climate, possibly several times. And in mild climates like southern California, over and over.
Still, reblooming irises used to be brushed off by iris aficionados as second-rate--in a word, they got no respect. Well, if you haven't invited a rebloomer into your garden, you are truly missing something.
Last November when the rest of the garden was preparing for dormancy, my husband and I marveled at the many buds of 'Immortality' that opened one after the other, all sublimely scented with a delicious sweet-fruitiness. The winner of numerous awards, 'Immortality' is a standout among rebloomers. The timing and number of reblooms depends on the region of the country, but it reblooms as far north as USDA Zone 3. And in warm climes, it's considered an ever-bloomer. That's not shabby.
The number of beautiful rebloomers is growing. When you select a rebloomer, first find out how it performs in your area. All cultivars vary in their reblooms according to climate and their own genetic makeup. A reputable nursery will be able to recommend cultivars most likely to rebloom in your region or zone.
Reblooming irises, also called remontants, may not reliably rebloom every year, possibly due to vagaries in the weather, and sometimes due to lack of nourishment. Whereas many gardeners do little with once-blooming irises other than weed the bed periodically and divide them every few to several years, rebloomers could use a little extra help. Feed after the first bloom and again in summer, using a low-nitrogen fertilizer. Cut the old stalks as soon as flowering has completed. Water during dry periods.
When the great garden writer Henry Mitchell's irises bloomed, he took vacation time to sit in his garden and enjoy. From time to time, he fretted over the muddy colors of some cultivars, choosing only the ones that were clear and translucent. That's how much these beautiful perennials meant to him. With these rebloomers, he could have vacationed nearly all season long.