Where can I find the seeds for the mage in the Severed Hand?

I think I found them in Lower Dorn's Deep... How's that for vague? Sorry...

If you gather the items for the garden -seeds, animals (must be purchased), and something else(forgot,you'll know when you find them)in lower Dorns Deep and take them back to the severed hand I think you'll find it was worth it exp-wise. Mucho worth it

And there's a barrel of pure water!