Answer: Most perennials are started in midsummer so that they can be large enough by fall to have a root sytem capable of withstanding the freeze and thaw cycles of fall (and spring), as well as build up sufficient reserves. In my experience, most can be started just fine in the spring if you pay attention to soil temperatures. This allows extra time so the plants are even bigger and stronger going into winter and put on an improved performance the following year. Any seeds requiring a chill period, in case that is why you care thinking of fall planting, can be cold stratified in the refrigerator.
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