Yes, it will damage the lilies because they need to keep their leaves/stalks until they die back naturally to feed the bulb for next year.

Here is what I did the other day for aphids, got the recipe on the antique roses forum. Also you can jet them off with the hose, that might ruin the blooms (you didn't say which part of the plant they were on).

Mix one teaspoon of liquid dishsoap with one quart of water in a regular spray bottle and give it to them good. They should turn black and die in a week (don't know about flying ones). I didn't know about that when they were bothering a few roses in late spring so blasted them off with the jet on the hose and hand picked the rest. But I sprayed my phlox just about 5 days ago where they've appeared (must be low on ladybugs around here because they're supposed to take care of aphids when they come in early summer) with the solution, and they have disappeared. Didn't have to repeat but you can daily.

I'm surprised Sevin didn't zap them. Did you use 2 fluid ounces per gallon? Also Bayer Advanced Rose and Flower Insect Killer says on the label it's for aphids. HD was out of it so I ordered a bunch online because it works on Japanese Beetles.

But here is the caveat. It kills bees. Now I haven't seen any bees in my lily blooms, just flies and occasional Jap beetle. The product contains imidacloprid and has a residual effect that lasts up to possibly 30 days. That will disorient and incapacitate bees days later. So be careful if you decide to try that, comes in a 24 oz ready mixed bottle, don't forget to shake. I forgot to shake my Sevin concentrate.

I'd try the soapy water first, then if they are still creeping you out, try the Bayer. You could cut off the blooms but don't cut them down except as a last resort. My Bayer is insurance if the JB's swarm here shortly, and I only intend to spray plants that aren't blooming (cut the buds and blooms all off my roses until the beetles are done).

Thanks so much. I'm still scratching from yesterday and I feel like I am infested with little creepy bugs. YucK! But I'll try the soapy water tomorrow. I shook the Sevin, but that's pretty icky stuff and it scares me so I'll try the soap. Thanks again.

Hope it works. I talked here and to a fellow who manages the garden section of one of our best nurseries. Asked what they sprayed. Sevin. Do you suit up, what do you spray with? Oh, they just put those warnings in because they're afraid of lawsuits. I've been doing this for 30 years and never had a problem. What do you use for a sprayer? The pump kind. Don't you worry about getting it on your clothes or skin. No, didn't bother him, sure he washes up as best he can but it's part of his job so I doubt he can go and take a shower.

I'll only use Sevin as a last resort now. If it rains, it doesn't hold but it did seem to help some, but if I have to keep doing it every week, forget it. This is for Japanese Beetles. It drops them in about 1/2 hour.

what about lotus leaves will they die if i spray soap solution?

I have been hosing them off best I can, using Garden Safe Insecticidal soap and still have them. I can't get every leaf! I am at my wits end. Now I know where my lilies have been disappearing to every year! I need something to kill them once and for all. I've had my lily trees for years and keep getting and infestation every year!