I am new to this website and have enjoyed so much reading many of the excellent forums. I have a problem I hope someone can help me with. I am not new to gardening but for the first time this year I planted butterfly weed and I immediately got Monarch caterpillars and saw my first one come out of its cocoon day before yesterday. It was so exciting and I was absolutely delighted.
Then this morning I took two of my five dogs to the vet and they found fleas on the Cavalier King Charles spaniel. (I have two male Cavaliers and three retired racing greyhounds -- two males and one female.) My dogs have always been on Frontline Plus but apparently its effectiveness is diminishing with time. I now have the Cavaliers on Comfortis, but I am reluctant to change the greyhounds' preventative because Comfortis has not been on the market that long and greyhounds often have odd (i.e., bad)reactions to products that don't bother other breeds.
Since this is Houston, I also have the inevitable giant outdoor cockroaches. I don't have a problem with flies because I use the Rescue fly traps (and I pick up the poop religiously). Before I planted the butterfly weed I bought a bag of insecticide (bifenthrin) to sprinkle around the perimeter of the house. It will also kill fleas if sprinkled in the grass. I have not opened the bag because now I am afraid it will kill the caterpillars.
Is there anything I can use to kill the fleas (and any other obnoxious pests) that won't harm the caterpillars. I don't want to give up the butterflies. They're like an addiction.