Posted: 05/02/2014 at 09:40
GW magazine did an article on crop rotation in the January issue. According to that - sweetcorn is in the grass group, courgettes in the cucurbit with cucumber, melon & pumpkin, spinich is in the beet group with beetroot and chard. It also showed how to double crop over a three year cycle. I could take a photo of the relevant bits and post on here but don't know if it would be allowed.