Insect specialization, pests and predators/beneficials
Monarch butterfly caterpillars only eat Asclepias (milkweed.) So the following concepts are not so different, but definitely interesting.
Chartreuse sweet potato vine always gets white flies, and the wildling morning glories (so talking about two different species of Ipomoea) always have something wrong with them, often the same thing, sometimes aphids. Can't decide if they're attracting these pests to the yard or luring them away from other plants. I've seen no evidence of the pest problems on these plants spreading to other plants. These pests rarely kill these plants so I suspect whatever eats them is out there, doing some of that. No way I know what every bug in the yard is...
If you build it, they will come...
In order for beneficial, predatory bugs to come to your garden, you'll need some pests. If you're out there all the time, micro-managing with 'cide, soap, oil, whatever, there could be some serious difficulty with achieving a balance of the natural order of things. Obviously, it's killing the food source of the desired "hero" bug. And if your hero is on the scene, he's probably going to be killed too. Not saying anyone shouldn't put up a fight if pests threaten to actually kill plants you've bought or plants you need to put food on the table, and I don't have the same attitude regarding house plants, but just saying that it's probably not be the best idea, long-term, to try to be proactive about every chewed leaf or critter on ornamental plants.
Found an interesting article at CO State Univ about how lady bugs have specialized diets, and this similar article about predatory bugs in general. So if one can ID their lady bug, might it be a clue about what pests are present? Also seems like good info to have if you're inclined to spend money buying beneficial bugs/insects. You'd want to buy a kind that will eat the pests you have.
What do you think?