It may very well be slugs. They love basil. To find out if it is, put out a few shallow dishes with raised edges (like the sauce cups you get a restaurants) and fill them about 3/4ths full with beer. Put them out near your basil plants right as it gets dark. Check the cups in the morning, and if there are drowned slugs in the beer, then you know what it is.

My mother used to do this with her gerber daisies and her basil plants. She said that slugs love beer and they would get into the cup/dish to get to it and then get drunk and drown lol. I havent done any research on this, but it always worked for her.

I feel your pain! Something always eats my basil, and it's MINE! I love using it in recipes and hate wasting the parts that have bug koodies on them! Whatever it is, eats my mint (which I don't care about) too! Parsley seems immune.

I might just try that beer trick!

Thanks everyone for the replies....I personally don't think it's slugs...I haven't seen any slime..... I saw a cricket hiding there once but I haven't heard anyone call out cricket as something that eats basil. I have spread used tea ground and dry mint around basil and the eating seemed to have reduced....am keeping an eye on it for now:-)

I have the same problem and twice now found toads lurking among the basil seedlings. Could they be the problem, or are they feeding on whatever is snacking on my basil plants?

Something munched on my basil too and i immediately blamed slugs so I set out handy dandy beer traps but the next morning it was obvious no slugs had come to the party. I sprinkled crushed up egg shells all around just in case slugs were lurking nearby. I am waiting for my local feed and supply to get in DE...that will be so much easier than saving egg shells!

What else would eat away the leaves?

Josko- Toads wouldn't eat the basil. They would be more interested in the bugs eating the basil.

Mari- Critters with four-legs also eat plants.

FataMorgana

Snails were eating my basil plants until I used cardboard cups without bottom to protect them. The snails won't climb on the cardboard to get to the leaves. Hope this helps.

I have discovered that small green caterpillars like my basil - I have caught them eating the fresh leaves!

I now spray the leaves lightly with insect spray - that helps

If you can see the bugs, you are better off just hand-picking and squashing them as opposed to insecticide on food plants.

FataMorgana

I have 6 basil plants in a long planter box on a ledge about 2-3 feet off the ground. The plants did extremely well, but here is the mystery. Every few days now I find the box is down on the driveway, about 8" out from the ledge. It is upright, never tipped over, but several of the basil stems are broken, always on the side between the plants and the ledge. Is some large critter doing this, and wouldn't that mean the box would be tipped over? I can't imagine any animal but a raccoon could do this, but that is a stretch. The leaves are not nibbled, but the tough stems are broken. I'm beginning to feel uneasy about making the pesto . . .

I just caught a squirrel eating my basil! It had leaves in both front paws and hanging out of its mouth. Mystery solved...it has already eaten 2 whole plants down to the dirt and half of another. It's been the squirrel all along!