Answer: Some pesty critters feed only at night so you might want to go out after dark with a flashlight to see if you can find the pests. Sometimes caterpillars will feed on leaves and then migrate elsewhere so all you're left with is the damage and not the pests. It's hard to go after a pest that you cannot see. Try the after dark process. You may find slugs or snails feeding. If so, slug bait is your best approach for control.
Best wishes with your morning glories.
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