My zinnias are taking a hit as well ... as are surrounding plants! I've actually only SEEN slugs and caterpillars (hopefully "good" ones and not tent caterpillars but I haven't had a chance to look them up yet), not Japanese beetles (those are on the blueberry bushes so I have them, just haven't seen them on the zinnias). My guess would be that if it's beetles, you'd see them in the daylight hours. If you aren't physically seeing them, I would consider maybe slugs (especially if the plants are still small and low) or caterpillars.

Because mine is a garden for butterflies, I (a) can't complain about most of the caterpillars since without them, there are no butterflies, and (b) can't spray with anything toxic, so I'm just resigned to some damage. But I must say, there is a tremendous amount of munching damage at what seems an earlier than usual stage of the summer, which I attribute (the slugs, at least) to the wet conditions we've had. You might try going outside after dark, or before dawn, with a flashlight to see if you can actually SEE the culprits at work. Then you'll have a better idea of how to treat.

Good luck! (Oh, and I meant to add, I think the beetles create more of a lace-like effect, whereas caterpillars and slugs will eat whole, clean chunks out of a leaf, if that helps.)

If you're going to use a product like Sevin, which is highly toxic to bees, it's really important to know what insect you're going after. No sense applying toxins that don't work for the actual culprit that's doing the damage, because it doesn't help the problem and yet you're getting all the same negative environmental side effects.

I know it's hard to see a plant you've spent time and effort or money on being attacked, but almost none of the standard garden pests actually *destroy* their "host plants" - the plants almost always recover and re-grow. Taking a day or 2 to identify the problem is time well spent.

Sorry if this sounds like a lecture! I very occasionally resort to chemicals, and I think they have their place - so I'm not trying to make any point other than that you really need to be very careful with those products.

It's kind of early for Japanese Beetles. Rabbits may be the culprit, do you have them in your garden? They love to eat tiny zinnia seedlings...

I've never had Zinnias munched on much, but have had other problems with them (like powdery mildew). It sounds like it might be slugs, which usually feed at night. In that case you can get a product called Sluggo which is a very effective slug bait that is safe for pets, children, toads and the other insects.

I agree that it's discouraging to see your plants get damaged, but this is an unavoidable part of gardening and it's impossible to have a perfect garden. So far this year I've lost a couple plants to a raging fungus and have had to spray regularly (with an organic copper fungicide) to prevent more losses, several Rudbeckia have wilted and died from something gnawing at the roots, the pretty blue Hosta are scorched and drying up from too much sun, etc. etc.

It is worth a little detective work to try to figure out what's happening and use the least poisonous way to deal with the problem.

Agree on the Japanese beetles (I think of them as mid-July) but voila! They are piling up on the leaves of my blueberry bushes as we speak. I was surprised to see them (but see them you definitely can!) So they are a possiblity, but I do think you would see them at work. I suspect slugs or caterpillars, but bunnies are a possibility, too (though wouldn't they eat the whole seeding?)

Terrene -- what is the organic fungicide you use? Would it be safe for bees and butterflies? My monarda are being overcome (not surprisingly with this weather!) by powdery mildew and they haven't even started blooming yet! I'd like to try to do something but it's a bird and butterfly garden and full of both right now, so I have to be careful... I know there are also baking soda (I think?) solutions you can use on mildew?? Anyone know what the recipe is for those??

Thanks everyone! The zinnias are planted near low growing euonymous shrubs that harbor slugs deep down inside the middle of the plant and slugs could be the culprit. I have never seen rabbits around here in the 17 years that I have been here. I bought a slug product at Home Depot after work today and sprinkled it around the area. I also bought some more zinnias to replace the ravaged ones. The zinnias planted on the other side of the house( a bit farther away from some euonymous shrubs) do have some bites taken out of them and I have seen a few japanese beetles flying around outside a few minutes ago while I was out there doing garden work so I suspect they are munching as well. Thanks again, Richie

Ctlady - the product is called "Soap Shield" by Gardens Alive. It is a copper fungicide without sulfur. It breaks down into copper and fatty acids, which are nutrients for plants and the soil micro-organisms. I also garden for the pollinators and insects, and Garden's Alive makes all organic products, so I assume it's safe for the critters.

I am mixing a somewhat dilute solution and spraying all Peonies, Phlox, Monarda, Asclepias and some Rudbeckia, even the plants that haven't shown any symptoms yet. I spray the foliage, not flowers, although most of these plants aren't flowering right now. The Asclepias is though, and I see lots of bees on that.

You need to re-apply it after rain - maybe not a light rain, but probably a medium-heavy rain.

Here is a link that might be useful: Soap Shield Fungicidal soap

If it is slugs another method that works quite well is beer. I've used it for years and years and it never fails to work.

All you need is quite a few very shallow bowls and the cheapest beer you can find. Place the shallow bowls strategically around the plants that are being attacked by the slugs, then fill the bowls with the beer.

Next morning you will have tons and tons of drowned slugs in the bowls of beer. I have an old, very small sieve I use to take the slugs out of the beer and drop them into an empty coffee can. Every other day I just pour the beer on the ground from the bowls and add more.

Never failed to end the slug problem within 3 weeks.

When my son was young, around 10, (he's 30 now), he would go outside after 10pm with a flashlight and watch the slugs fight to get into the bowls of beer. The things just couldn't resist the bowls of beer.

Fran

OK, here's the latest. Just went out to check on the zinnias after putting down the slug bait last night. There was some slimy shiny areas near the edge of the slug bait border and there were flies on the slime. I am asssuming the slugs went on the bait and totally dissolved! Only damage to one zinnias is from a dog or someone walking on the sidewalk stepping on one. Jopefully I got them This weekend I am going to replace the eaten zinnias. Richie

Sounds as if you've found your culprits - congratulations! (Did you know that if you sprinkle a slug with table salt it will dissolve before your eyes. A fascinating, if nauseating scientific fact, but I've actually seen people do it. It IS effective (and yes, you do end up with a "shiny" blob when it's done. Yuck!)

Ya know, I thought about putting alittle salted water in the euonymous' but wasn't sure that could handle it or not. The slugs are hiding out deep inside the centers and obviuosly make it through the winter in them too.

Ick. I used to use beer in my gardens, but it's a pretty labor intensive method and nauseating to boot. Now I use sluggo - needs to be reapplied after a rain but it works like a charm and is totally nontoxic to all but slugs.

The initial investment is pretty high compared to beer - something like 20 bucks for a big jug of the stuff - but one jug lasts at least a year, maybe 2, depending on the weather.

Hi. I am a bi-zone gardener, just learning the ropes up here in Massachusetts.

If it is slugs eating the zinnias, you only need a small bowl of left-over beer and they will belly up to that. The critters drown themselves in it. Down south, we knew they were there from the slime trails across the pavement.

Also, I've discovered that my maltese will rub/roll on both slugs and earthworms, absolutely disgusting but true. So if you have a small dog, watch what it gets on its coat!

Ha! My dog used to roll on and dig for worms in my garden in Virginia!