The only way I can see it getting fixed is for the government to enforce the regulations across the board. Which is what you were saying. This will force the industry to start paying a little more to get legal citizens interested in the jobs. Landscaping jobs would just become more expensive to the clientele. That would squeeze the industry a bit, because a small segment of people just wouldn't hire a landscaper at the higher price. After the industry shrinks ever so slightly, and people become used to higher prices, it would settle into normal. At least that's how I see it. An individual business would have to do it for less profit, until the government enforces it across the board. Landscaping jobs would be towards the more privileged clientele. And in a related area, a few more people would be mowing their own lawns on top of it.
I would say it probably would be good to do it in gradations of punishment. But there will be individual companies(no matter how gradual it is) who will take that risk no matter how high it gets. The reason they will take that risk is because those companies are budgeted to the bone and haven't reached a level of cushion, to afford to raise wages and temporarily lose money before the higher prices start becoming more widely paid. Those companies will likely bite the bullet and go out of business if they get caught when the penalty gets serious.
Of course there will be the risk takers just trying to get away with it, but I think the larger population of risk takers will be at cause of necessity. My guess is those companies who have to take the risk and get caught would shrink the industry somewhat in accordance with those clients who won't be doing the landscaping at the higher prices. So that will work out fairly well for the market. No matter how you do it, there will be a number of companies who suffer/go out of business. But it won't change until it is enforced. If the whole industry cuts their budget a little bit(suppliers of materials... rock, gravel, sod, plants, etc.) it would be a little easier on the landscapers, but that would have to be voluntary, and temporary. I can't really see the suppliers being motivated, seeing as how they are going to sell a few less materials when it is all said and done.
Of course there will be automation, which will take away jobs. Some day your handy dandy gardener will be a robot. It would push lawnmowing a little faster towards robots as well. I can see robot lawnmowers having a manual mode for the trim work. Tree work might move faster towards automation, which wouldn't be a bad thing.
If you want to apply this to other industries then food and cheap motels will cost more. There won't really be a cheap motel.
But then again we are all Cads taking advantage according to NoblesseObligeCane. The reality is you would lose money if you had to pay more without getting more. The profit margins don't allow you to increase your wages that much. You would have to hire tons of guys and get tons of jobs to make any kind of money. You would become the Walmart of Landscaping. Not what I or any others want to do. So it's not exactly the old everyone does it defense.
