Even though you have a greenhouse most small greenhouses will not protect plants when it goes down to even 20 without heat at night. To help with this I suggest you put at least 50 gallons of water in it for heat storage! This will maintain a above freezing temp inside even if it goes down to 20. It will also help with the high temps by absorbing some of the excess heat! I know that is a small greenhouse but you can use the 50 gallon drum for a table!
I enjoy fishing ,gardening and a solar greenhouse! carpet installation repair and sales for over 45 years! I am the inventor of the Bobber With A Brain - Fishing Bobber!