Well, I did start this ‘blog with the partial intent that it would help me document what I learn in the course of gardening. So today I had to rewire a thing I understood about particular bugs I’ve seen in the yard. I’ve always noticed clusters of red-black bugs on various plants. And I’d assumed they were a form of assassin bug, a predatory bug that nabs other bugs and sucks the juices out of them. I think I got that impression because I do indeed have some assassin bugs, and they are red and black, and I have seen them with captured bees and whatnot.
So I didn’t think much about the cluster of red and black bugs on my cherry tomatoes. I assumed they were happily nabbing pests that dropped by. Little did I know they ARE the pests.
Fortunately (can I say that about this situation??) Carla of austinurbangardens.com fame has them and asked her people what they were. After boldly jumping in and naïvely asserting they were assassin bugs, I went back to read her other comments on the subject. And I had to agree… they are leaf-footed bugs, a form of stink bug that sucks not the life out of other bugs, but out of tomatoes… AND peppers AND passion vines AND a number of other things I have growing here.
I suppose these pests only really matter to me now that I have vegetables I will fight to protect like my own son. And that’s just what I did tonight. Armed with a spray bottle mixture of one part Seventh Generation dish soap to 4 or maybe more parts water, I doused as many of the buggers as I could find. I’d heard these bugs are hard to control with anything but insecticide, but most bugs can’t withstand soap since it breaks down the waxy layer that allows them to repel water and breathe. So, they drown.
Doing some reading, it appears my mixture was a little heavy on the soap side, and probably should have been a different type of soap, too. Like Dr. Bronners castile soap. I’m sure what I used won’t kill my plants – I ran the sprinkler over them to wash it off this evening – but I don’t want to take any chances.
There are lots of homebrew insecticidal soaps mentioned on the internet, but it seems the ideal recipe is 1-2 tablespoons of soap per quart of water. For a little extra oomph, the water can be used to boil some noxious (to bugs) herbs (cayenne or other hot peppers, ginger and garlic are all mentioned) before it is cooled and soap is added. The mixture can be sprayed on the leaves, undersides of leaves and stems where bugs hide. It is a contact poison to bugs, and kills them indiscriminately. Bees, beneficial bugs and spiders would all die from this mixture, too.
But it is non-toxic to humans, and safe for plants if it isn’t applied under full-sun. One site mentioned not using it more than once a week, but didn’t give a reason.
Tomorrow I’ll check to see what the mortality rate was with my soap mixture. Hopefully the count doesn’t include any of my plants.