It should be a great idea, but I feel like the quantities involved are too vastly different.

I’m seeing estimates of 300kW/hectare (30MW/km² or 77MW/mile²) for heating glasshouses. With individual datacentres frequently confirming multiple gigawatts, the land area required just doesn’t match up.

This is not to say it isn’t worth considering, but it would be a rounding error in the datacentre’s heat output before you ran out of space to build more glasshouses.

There’s a secondary concern of water consumption. You might extend that to ah but what if we could use that to grow the plants too? but the evaporated cooling water out of one of these systems tends to be anything but clean. Maybe that’s a more solvable problem.