1 tablespoon of liquid dishwashing detergent
1 cup of vegetable cooking oil.
To make spray mix 1 to 2 1/2 teaspoons of the oil/ detergent mixture with 1 cup of water.
Apply once every 7 days covering both side of leaves.
The next step is not really needed but it does help insure a complete 1st kill. After you spray your
plants then take diatomaceous earth (fresh water) place some in a old sock. Tie the sock to the end of something like a broom handle. While holding the sock away from you take a switch and pop the sock. The DE will lightly float out and cover your
plants. The oil will help hold it to the leaves.
BTW One year we got hit real hard with fleas and ticks. The sock/ diatomaceous earth did the trick. I put down about 5 pounds in the dogs area--about 80 feet by 50 feet. In the house I used 20 Mule Team Borxo Laundry soap. Worked that into all of the cracks etc in the funiture and into the carpet. 10 days later not a flea.