Answer: Based on your description of broken stalks and eaten flowers, combined with the height of the plants, I would suspect deer. If you are seeing deer in your garden area then that is probably the culprit. Please keep in mind that deer resistant does not mean deer proof -- deer are adaptable and will learn to eat new plants over time and local populations may have different plant preferences. If it is deer damage, the most reliable long term preventive is a tall fence. In the meantime you might have success using one of the commercially formulated spray on repellents; these are sold at garden centers and nurseries and should be applied and reapplied per the label directions. Also, some gardeners report they work better if different products are alternated. I'm sorry about your phlox.
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