Ask and you shall get. http://www.greners.com/grow-tents/br...ent-dr300.html
What is the largest grow tent for sale on the market? I am looking for a minimum of 10 by 10. Does anyone know of a place that makes custom tents?
Secret Jardin makes a 10'x20'. You can also daisy chain them together and remove the partition walls to make as large of a tent you would want.