Sounds like onion white rot. I've had that before and it makes the onions go all soft and slimy, with a white mold round the roots. There isn't anything you can do about it, according to my garden problems book, but you mustn't grow onions in the same place as the rotten ones for at least 8 years!! The disease is VERY infectious, and that's why everybody on the allotments is having the same problems. Sorry for the bad news. Even if you pull them all up now, the disease will have affected most of them and they'll probably go rotten anyway!! There are a couple of disease resistant types of onion, so you'll have to try those next year----but NOT in the same area of your allotment!! Annie (Cumbria)

many thanks for your reply :-( sad to here that they was coming on fine pulled them up to save the other to many to lose had a bad year last year with the weather rain and could not dry them out. many thanks again IAN