Your container plants won't survive the colder days of fall sitting out your porch. Bring perennials indoors, but first make sure they are free of pests and diseases so you don't endanger your houseplants. Place the perennials in a window where they'll receive their proper allotment of light. Some plants—for instance, rosemary—go dormant in the winter and can be kept in a garage or basement until the growing season begins.
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