This is the third year for my 18' x 28' greenhouse. I love it! But like most greenhouse owners, was out of room my second year! So this year, I had a 16' long cold frame added along the side of the garden house attached to the greenhouse. What a perfect solution for the overflowing perennials.
The warm, sunny days have been few and far between, so will let you know how it works once things heat up (July? August? ha!)
Also added two rows of metal tubing (conduit)on each side for hanging baskets. The greenhouse is just beautiful now!