Answer: I'd vote for pesky slugs or snails in the garden. They feed at night and in the early morning so you rarely see them. If there are no insects on your plants during the day, the most likely cause of the damage would be slugs or snails. You can use bait such as Sluggo, or you can make traps by inverting terra cotta pots and propping them up with a stone or stick. Slugs and snails seek out moist, dark places to hide and will crawl in at night. You can scrape them out in the morning and reset the traps. If you keep at it, you'll eventually trap them all.
Best wishes with your garden!
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