Agreed. Container-grown jade is much more manageable!
We didn't plant the jade in the ground ourselves. The people we purchased this house from in 1997 said it had already been in place when *they* moved in in 1976, and that it was "large" then.
Thus the ≥ 40 y.o. age estimate.
I have seen good-sized specimens of Crassula in large glazed containers (the $$$ kind which resemble classic pottery, with the green crackle glaze). The trunks were maybe 5 to 6 inches in diameter, and the container maybe 24 to 26. But the only places I've lived when I knew what jade plant was called were Atlanta and the Bay Area, so I don't know a reasonably achieveable (?) size for a northern-grown Crassula in a container.
If you're used to babying tomatoes along, yummy water pigs that they are, you'll think for sure that you're killing that poor jade plant by *not* watering it like the tomatoes. Rest assured: here in the dry season (usually April through October), some jade plants in the open are lucky to get any water at all, in areas which regularly experience temps in the 80s and 90s. I'm not recommending such a watering regime--obviously mine get a little more water than that--but it does give a new perspective on the function of those fat little water-saving leaves!
Sunset Zone 17, USDA Zone 9