Well I've proven the crop rotation theory...

When I was outside earlier on I had another look at my brocolli's which are coming along nicely. However, it is becoming really apparent that two of them are trailing far behind the others. It was then I realised that when I planted them back in April I didn't take into account that I was putting them into a spot where I had brocolli's over summer! So the heads on those two are maybe a centimetre in diameter and the others are up to about 3cm in diameter and much healthier looking. Oh well, good to test these theories instead of believing everything you read eh (even if EVERY book says so...)??!!