Hey.👋 so getting down to 59 is really tough spot to be...its hard fighting to keep an area warm, but anywhere near 61 and lower you're gonna have to be wary of mold and mildews, or botrytis. If a tent isn't in your budget maybe you could visquine where that door is and try to insulate any drafts? Or build a makeshift tent...something to just sort of contain everything. I grew in my shed once and in the cold months i had to run the heater all night and most of the day too. Good luck Happy growing ✌️