The basil was growing blissfully. And the mint was minty fresh. When one day, I began to notice some tiny holes in the leaves. Hm. As if something was munching on them a little bit. But not too bad. Literally overnight, the holes became gaping and the leaves looked positively chewed-on! Little black spots peppered the plant here and there. I began to google furiously to find out what bug was marring my herbs and what organic (human tummy safe) pesticide I could use to make sure it kept its little mandibles off my crop! 
I tried a homemade organic pesticide made of hot pepper, ginger, garlic, and a good dash of cayenne pepper. (Put these in a pot and boil like a tea, then cool and spray onto plants.) This spray must have just made the plants a little spicier, maybe even tastier, because the bugs were not deterred. Chomping and more chomping occurred. Finally, the telltale black spots (turns out that's bug poo poo) helped reveal the identity of...the greedy Cabbage Looper caterpillar!!
These little critters hatch from eggs laid by moths on the underneath side of the leaves. They start out so small you can't see them at first but eat so fast they double in size practically daily. They were the exact same green color as my plants and held absolutely still when they were eating so were very camoflaged. You need to examine the underside of your leaves to find them. When I tried to pluck one off a leaf, he reared up and swung his head and forelegs around surprisingly quick for a caterpillar and tried to grab onto my fingers as if to scare me off. Which he did. Then he kind of hung in the air like a stallion pawing, challenging me to just dare to try that again. Lively little guys these. Not your amiable slow moving little caterpillar.
Moving on from hot pepper garlic ginger spray, I came across diatomaceous earth next. This stuff is gleaned from the bottom of the ocean and is made from tiny plant matter whose atomic structure is in the shape of a diatom. Because of the diatom shape, this dust has sharp corners which cut a juicy bug's exoskeleton and basically cause it to bleed to death over a period of about 48 hours. I bought some of this and discovered it's rather labor-intensive to apply and also started to feel bad for the little caterpillars I began to see suffering and limping along due to coming in contact with it. Not the most humane way to kill something..akin to being killed by being slashed thousands of times with a razor blade. I began to mercy-kill the little things by plucking and smushing underfoot.
A more effective organic pesticide was identified..BT or Bacillus thuringiensis, a "bacteria that infects the gut of soft bodied caterpillars" and causes them to die 3-5 days after eating leaves that have been sprayed with it. Three to five days is the catch. Until they finally get sick and die, they can dessimate your plants in the meantime (as you can see from the picture below.) So keep plucking and smushing underfoot as your firstline method of pest control. And when you spray, BE SURE to spray the underneath side of leaves, where caterpillars eat. Best way to do this is to tilt the pot sideways to make the underside of the leaves more accessible while you spray from the side.
As you can see, the mint plant has made a full recovery after treatment with BT and is growing nicely. The basil is pretty much back to normal, too, with only a little bit of chewed-on-ness from some other bug I can't identify but who isn't eating a whole lot.
However, in the meantime, one of my pots of lemon basil has been all but wiped out by another kind of caterpillar which is brown and slower moving than the cabbage looper. I collected about five or six of them one night and put them in a jar with a lid so I could try to identify them when I had time. And..I haven't had time yet. But these caterpillars seemed to not be very affected by the BT since this pot was sprayed several times with BT....(?) Another weird thing..three other pots of lemon basil weren't touched by these brown caterpillars. So, the score so far is: Bugs 1, Winnow 1. 
