Safer soap will kill them, but you have to get it on them, meaning spray underside of every infested leaf. Use a tank sprayer, not a squirt bottle. Next best choice would be a house and garden aerosol containing pyrethrins, which break down in a day. These are in grocery stores.(Read fine print for ingredients.) Don't use anything persistent because you will kill beneficial insects. In my yard, wasps keep the rose slugs under control. No need to spray the plants that aren't infected. As you have learned, the Bayer All-in-One doesn't work well at all. Also the insecticide in it can cause outbreaks of spider mites. If you need a fungicide, get the spray concentrate Bayer Disease Control for Roses, Flowers and Shrubs and apply it with a tank sprayer every two weeks during blackspot season. It is not widely distributed. Get it online, or maybe at Lowe's. There is only one ingredient, tebuconazole. Allow 24 hours for the soap spray to kill.

I too love my garden spiders... If I ever get JBs in my garden, I would want a gigantic fuzzy tarantula hunter spider with banded legs, hahaha for catching them... I am not looking forward to getting those JBs... Well, terry I am having great difficulty having wasps and bees in my garden...I think my next door neighbors are all killing them before they have the chance to settle in my garden...Everything starting in late July is so far deserted, the bee balm the lavender, the oregano, the nepata, sigh! once in a blue moon I'll get a handful of tiny wasps and native bees. But maddeningly enough they will disappear again! It's pretty sad when most of the fliers are...ugh! flies! This is why it's so important to save the bees. but thank goodness at least the spiders aren't killed off.. I think it's because they don't fly off to a different territory but stay in my rose bushes... I love the huge cobwebs they spin at the base of all my large rose bushes... It keeps away the aphids... If only they would go to the top of my roses to keep away the thrips...But my guess is that they don't like hot pepper spray I keep spraying on my blooms, LOL!

Salt kills slugs, for sure, but northspruce is right that it's not good for the soil (or plants). I don't know why I didn't think to mention this before (probably because I'm still at the ammonia spray stage of warfare), but Lee Valley Tools sells a copper roll for slug control. It doesn't kill slugs, but it keeps them off your plants. Copper gives slugs an electric shock when they touch it. If you get the copper around your plants before the slugs get into the nooks and crannies of the leaf axils (early spring), then the plants are safe. (If you put it on after the slugs are on the plant, you just encourage them to stay! The roll is 5 inches wide, but I imagine you could cut that down. It's fairly pricey, but you wouldn't have to replace the copper wire each year. Although it would be a hastle to put the stuff around the whole garden, it could be useful for special plants, or for plants that are the most susceptible to slug damage. I've also heard that you can get rolls of copper sheeting from metal suppliers, and cut strips yourself. The copper kitchen scrub pads can also be unraveled and the strands placed around the plant. Heck, you could even surround your very special plants with pennies! I might try the Copper Blocker next year (too late this season...the slugs are already on the plants. Besides, my ammonia spray is ready to go!!) Here is a link that might be useful: Lee Valley's Copper Blocker

First, I find the best thing I did for myself, re slug control, was to keep all dark, damp areas (under deck, shady spot near base of house, etc...) super clear of weeds, large stones, planks of wood, etc.... As long as there is no place for them to hide during the day they don't seem to hang around. I learned this the hard way. I had some left over 2x4s from building our deck that I was too lazy to get rid of last summer so I stashed them under the deck. Once I finally pulled the boards out I hit the slug mother load (lode?). In fact, there were two slugs that were SO huge I couldn't bring myself to pick them up. I kept asking my hubby to get them (asking escalated quickly to demanding and then screeching). I thought I would throw up. Finally my husband came to check it out and said he couldn't see them. When he finally did lay his eyes on them he nearly jumped out of his shoes. He said he didn't see them because he was looking the typical "garden variety" quarter sized greasy little thing, not the wooly mammoths of the slug world. They looked like shiny, brown, VW bugs. They were surly too. As my husband finally tossed the last one into the street it turned and gave us the finger. Seriously, keep the area around the plants that they love super clear of debris. Those babies need some where to stay cool in the sun - take that away and they go away (mostly). Also, I do patrol for them twice a day but so, far, have only found a hand full of tiny ones.