Ants, scales and mealybugs are ruining everything

	This newly created and planted squash hill has been taken over by ants. Its almost guaranteed that anything growing in there will be attacked by mealybugs cared for by the ants. I am at wits end, I don't want to pour poison in the hills for fear of the plants absorbing it and it ending up in my body. What can be done, I have billions of ants everywhere and have noticed scales on a lot of my plants, from grumichama to firebush and natal plum. Nothing seems to kill the scales and these plants leaves are covered in the honeydew these things excrete. The leaves are also covered on sooty mold as a result of the honey dew.
	This poor Mexican petunia is being overtaken by barnacle scales, I often see ants associated with them, so I guess they must by excreting a kind of honeydew also.
	These natal plum (Carissa macrocarpa) leaves are infested with green scale, covered in honey dew and sooty mold. Nothing so far has helped, I've sprayed with bifenthrin, neem oil with perythrin. My firebush looks like someone has sprinkled sugar water over it, the honeydew is visible from quite a distance. I even discovered this pest of one of my beloved grumichama's ! I took a twig and scraped a lot of them off, but when I look the next day, there are more everywhere !