Answer: Irises will give you a fairly good length of bloom. Unlike when planting gladiola, staggering planting of iris will not be especially helpful in extending bloom time.
You may want to consider choosing more than one type of iris as there are several that will grow in your area including Louisiana, Dutch, and Spuria to name a few. They are usually fall planted, but can be planting anytime, especially if container-grown plants are used.
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