Posted: 17/06/2014 at 21:05
Some brassicas are eaten as salad leaves, when they are young. Nowhere does the OP say the seeds were supposed to be all lettuces. Nowhere does she state the contents - by botanical or common name - of the seed packet. She simply said they were mixed. She may find the leaves are now unpalatable, but they will not harm her.
All I can say is my original thought is that the OP has left the salad leaves too long before cropping them.
When you say I misread this post, do you mean your post?
Perhaps Mel will come back and tell us what her thought are now.