I’ve used Safer soap in the past, and, for the most part, it works pretty well. But it’s also more expensive than it needs to be, and comes in more packaging than I want.
So I grabbed what I thought was Seventh Generation soap the other day, and mixed it about 4-to-1 with water and sprayed a bunch of leaf-footed bugs on my cherry tomato plant. It definitely did in many of the bugs, but it also turns out to have done in many of the leaves on the plant. Within a few days many of the leaflets turned brown and the compound leaf turned yellow. I suspect many will fall off.
Turns out it was not Seventh Generation, it was Palmolive “Pure + Caring” (whatever that means.) One of the warnings on the bottle says not to use with bleach products… which means it might contain ammonia of some form. There’s no ingredient list, so I had no idea. I looked it up online, and the stuff appears to be a regular chemistry lab. Not sure how they justify calling this stuff “pure”. Especially if it kills plants, too*.
So, I’m resorting to using a dunk-tank method of pest management right now. Stink bugs and leaf-footed bugs seem easy to trick into jumping down from their tomato, so placing a little soapy swimming pool below them usually does the trick. I’ve been hand-plucking worms of various sorts and dropping them in, too, if my little tupperware container of trouble is nearby. Otherwise, it’s the shoe for them. No more giving hornworms a fair shot at crawling back to the plant from a long distance. I’ve found one too many of them with their wormy asses hanging out of a half-eaten green tomato.
*To be fair, now that I think about it, any heavy soap would probably disrupt normal transpiration processes of plants since the detergents would damage or clog leaf pores, or break down the water resistance leaves would have to keep them from “drowning” when wet. I think the trick is proper dilution of soap and perhaps washing down the plants afterward.