Answer: I'd venture to guess your plants have fallen victim to Spittle Bugs. These are really tiny little fellas that feed by sucking the juices out of stems and leaves. They protect themselves from predators by manufacturing a bubbly foam that disguises them, and makes them appear larger than they really are. Spittle Bugs can be hosed off plants with a strong stream of water. Your plants should recover from the attack. Be sure to rake up and destroy fallen leaves at the end of the season (just in case the Spittle Bugs have laid eggs on them).
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