It is a great treat to look in the garden in an off-season and find majestic stalks of iris. Re-blooming iris produce more than one crop of flowers. After the Spring season, you can have nice surprises until the first hard freeze.
Rebloomers are almost as easy to grow as ordinary iris. They have the same requirements of good, well-drained soil, but do need a little extra effort. You should fertilize in Spring and again after Spring bloom. You don't want the plants to go dormant, so water them during dry weather. Also, ordinary iris can be planted under deciduous trees because they primarily need sun prior to Spring bloom; rebloomers should have at least half a day of sun all year.
Other than doubling or tripling your pleasure with re-blooms, these iris are said to be more resistant to rot, grow much more vigorously, and have less spot and insect damage. Their foliage is in better condition in July and August, in part because of the extra water and food, but also because of their genetically controlled levels of plant hormones.
Reblooming iris are available by mail from specialty growers but at least one type - 'Immortality', a vigorous white variety - can be found in more general catalogs.
Rosemary Moyers, Smith County Master Gardener
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