[lathyrus_long]

Tomatoes, peppers, lettuce, culinary herbs, and many other plant species are grown profitably under hydroponic conditions. This is especially common in colder climates, to maximize the yield per square foot in expensive greenhouses. It's sometimes economic even outdoors though, like in regions with poor soil or scarce water, or to mitigate some (but not all) pests and pathogens. Here's a paper studying the economics of hydroponic greenhouse tomatoes in Florida:

https://svaec.ifas.ufl.edu/media/svaecifasufledu/docs/pdf/ag...

The theory is the same regardless of the plant species, but irrigation equipment and consumables targeting the cannabis industry tend to be quite expensive, sometimes because the higher-value crop justified that, sometimes for no good reason. The lighting requirements for cannabis are also unusual (very high PPFD, controlled photoperiod for non-autoflowering strains), so the greenhouses would need some reconfiguration. So the capital investment doesn't go to zero, but it's a big markdown.

A lot of graduates of top agronomy and horticulture programs (Cornell, etc.) also seem to have ended up in cannabis, I assume because the money was good. It will probably be better for society overall if this crash redirects their efforts to the food supply, though sad for them personally--vegetable growers are paid quite badly, even by the already dismal standards of the life sciences.

[dmix]

Thank you for this comment, it's very insightful.