there's an awful lot of lumber. if that is true underneath, then it may slow down root growth... which will impact everything else.
Reference a site for sunrise/sunset for your region. If >14 hours, it's not too late. Once you approach 14 hours of light, it's possible for a plant to go into bloom phase. Supplemental lighting in your greenhouse can extend this. Doesn't have to be super strong if it gets plenty of light during day..