Greenhouse bed between crops

I just finished the best crop of broccoli since I have been gardening in this location! (I am almost sick of eating broccoli. Or at least I am ready for a break from brassicas.) January 14 I started Apollo broccoli and February 20 I started Broccoli blend from Terretorial Seeds. I use a heat mat and lights at that time of year. Today I picked the last side buds and removed the plants. Now I am wondering what to add to this bed to get it ready for the next crop of broccoli for fall and winter. Any opinions out there?