I ran water over the leafs after I took all the ones with big holes and sides eaten off. I mean there was not one leaf with a hole left on plant. This morning more leafs have holes all over from just overnight. I also sprayed with soapy water afterwards after washing them even. So if it is a crawling insect, it did not kill or stop it by washing off. I also repotted it just after all this treatment. This morning after seeing it so bad, I gave up and sprinkled with Sevin 5 percent dust as it says you can sprinkle on vegetables of all sorts even lettuce. I know I must wash these leafs off in a colander over and over to use now but whatever is eating them takes one inch holes out of them overnight. These insects were not noticeable yesterday at all as I turned leafs upside down and all before spraying and then spraying with soapy water lightly.. They must crawl and attach themselves after dark or can not be hardly seen one.

Can you post a picture?
There are various leaf eating insects. But I have not seen them to attach sage noticeably. The only flying insect that eats leaves(that I know of) is flea beetle. The crawlers are: slugs, snails, caterpillars, various worms.

I can not post a picture. I will say this a half circle was out of two or three leafs. I mean a half moon. Also, when I look at back of leafs I notice little pin point dark spots. We will see what happens by tomorrow morning with both sides white with the sevin dust. It may not work immediately. I noticed his other plants for sale had those circles off the sides and holes. I should have not been weak and bought one, ha. I just wanted the sage I could use in dressing and my other sage plant is pineapple sage here in Fl is for placing in ice drinks etc and not for cooking. Also they bloom a long stem of red blooms so pineapple sage you can get over insect bites for the thrill of the blooms. I am just so sorry this sage is going to be bad for bugs. My place of purchase is a native plant nursery. He only uses the soapy water or DE. Dimaceous Earth is full of poison and my husband is a little afraid of having it in the garage stored. I probably should have used it but for sage I would think it would be more dangerous than Sevin 5 percent which must be completely washed off plant as it is.

Diatomaceous Earth full of poison? Do you have a pesticide that contains DE or do you have pure DE? If you have pure DE it should not contain any poison as it is a natural product composed of mainly silica. If it is pure try to use your DE against your sage pest.

Going to check the DE out. I know it was suppose to have poison and I bet I bought something with DE in it along with poison. Anyhow, good news. No new leaf destroyed since I placed the sevin dust on it compared to the day before leaf occurrence. I rather use the DE however as I think it would be safer since you mentioned I may not have the correct type and the main DE is without poison (pure try). What destroys the insects in that case? Silica is something that causes insects to stay away?

Personally, once you get them gone, there really isn't much that will go after sage. I wouldn't regularly use anything on them (I manage my house herbs with soapy water and occasional neem). Sounds like you just got something in there, and now that you have it gone, I wouldn't worry too much.

Also, what was the cold temps you were worried about with your sage. I know you said they were young, but sage is very hardy. You could also possibly get by by covering them with an empty plastic tote for insulation at night.

The DE must be food or horticultural grade. (There is also a DE manufactured for pool filters. You do not want that.) DE kills arthropods by scratching and dessicating their protective exoskeleton. When handled properly, it is perfectly safe.

The most dangerous poison you've mentioned is the Sevin. It's harmful to so many living things, including you! You should not touch or inhale it or ingest it. Don't get it on your clothes.

Too bad that we can't see a good picture of the leaves. The size, shape, and location of the damage can be quite telling.

I'm wondering if you've considered that the potting medium might be harboring your pests? Earwigs and pillbugs can do a lot of damage to foliage....and they come out at night. Some of your damage sounds typical of weevils or beetles, too.

To check if something is in the soil, place the plant (pot and all) in a large enough container to hold it plus a lot of water. Begin watering the plant, letting the outer container fill halfway with the drainage water. If there's anything in the soil, it should try to escape the flood in a few moments.

so far so good. There were a very few new bites day before yesterday and all looks the same again. After a few days, I am going to wash off all the Sevin I can and start using the soapy water and Neems. If I am going to be able to use the foliage, I need to start trying to get the poison off it. Then I will have to consider if I am a candidate for the bottled sage as usual at the grocery store, ha.

OK. I just read this post about the sage. I too am having a problem with something eating my sage leaves. My sage plant is in a raised garden with other herbs such as basil, thyme and oregano. There is also one tomato plant and one eggplant. Recently I've noticed my sage leaves are being eaten. I sprayed with a mixture of garlic, onion and cayenne. But whatever is eating them doesn't seem to be affected by this. All I see are some very, very small black specks and something that looks like a small web or cocoon looking thing. All too small to show with a picture (I tried). I'm at a loss.

Black specks(faeces) and webbing(cocoons) sound like evidence of a caterpillar of some description. Pick off leaves with the cocoons, and inspect for caterpillars. For a single plant a close look and hand picking should be plenty to get rid of the problem.

I too noticed something eating my pineapple save leaves. When I cut the plant and put it on a plate, a small green spider started running. I happily killed it. I can take a picture if you think it would be helpful. I will try to wrinse it off as you mentioned and add soapy water and see if that helps. Please advise. I am a new gardener and was shocked to see this happening to my plant.

Personally, I prefer to know what I'm going after before using anything on my herbs. That said, you obviously have something eating it, and spiders usually aren't the problem. Personally, I have some major issues with spiders, but don't bother them outside, as they usually eat the pests. Different from the spider mites spoken about above. Just from the holes, I don't know what you've got. At a guess, possibly earwigs or caterpillars eating that way.

I would pay close attention to it--many critters come out to munch at night, such as earwigs. Once you know what you've got, you can design a safe plan to stop. That said, a mild dishsoap solution won't hurt anything, though it's usually more effective against small things like aphids, which don't cause the damage I see. A good rinse with the garden hose also doesn't hurt anything.

I was going to say caterpillars or slugs; the holes seem too small to be snails - unless they are really tiny.

If it is caterpillars you can either hand-pick them or spray with BT. If it is snails or slugs, they can be deterred by hand picking them at night. It helps to put a copper band around the top of what looks like a pot in your photo.

Just had something start eating my sage, also. Was looking pretty good until a couple days ago. I had something eating up my young bean leaves about a month and a half ago, and had somebody say to put a jar in the ground with 1/2" of beer in it. I think it worked - trapped rolly pollies, a couple caterpillars, and earwigs (not sure if they were actually trapped, but many in there whenever I looked.) Might have also been a squirrel that ate the leaves, and I think the pooch scared him away in a week. But in either case, the plants recovered and nothing eating them now. So I'll put a pint ball jar in the raised bed also, to see if that helps - with 1/2" of beer in it. I also put chicken wire over the top so the pooch doesn't get into it.

My sage has a fuzzy texture, so I thought that might keep the caterpillars off it, but maybe not.

Scary???? An inchworm...Geometrid caterpillar.

I also have the same problem...but not understanding what is DE and BT ? Please explain the abbreviations to us garden newbies

Diatomaceous earth and Bacillus thuringiensis. DE is a dry powder that you spread to kill hard-bodied insects like ants and beetles, and Bt is a powder that you mix into a spray to kill caterpillars. They’re both totally organic, though DE is known to be harmful to bees and ladybugs.