As to your response that interstate traffic in drugs is massive, that is true but it may well be insufficient to support a commerce clause justification of the CSA, since the purpose of the commerce clause is to prevent states from interefering in interstate commerce. And anyway, my question was limited to whether someone growing for their own use could, under any reasonable interpretation, be subject to federal law.
Or to take drugs out of it, and make the crime one that everyone can agree is terrible: Do you think the federal carjacking law is constitutionally kosher?
It has repeatedly proven sufficient.