The leaves on a couple of the Setton onion sets were not looking as good or as well-developed as the others in the same bed. On closer inspection it was clear the young bulbs were probably dying so I pulled them to take a closer look. The bulbs were soft and spongy to the touch and when I peeled the outer skin away the bulb was transparent.
A very small worm (just about visible in the above photo, not a maggot) crawled out from one of the bulbs. The rest of the onions growing look OK, the leaves are much more developed and deep green. I decided to check the young bulbs by removing a little of the soil to expose the necks, they also feel spongy. Should I pull these out too? Can anyone shed any light on what this could be? I grew Setton and Red Baron last year (in a different bed) and did really well with them. I bought the sets this year from the same supplier.
I consulted my veg bible and looked at onion diseases and problems. I could see no evidence of white rot on the base of the young bulbs that I pulled, and I don’t think it could be onion fly because I couldn’t find any maggots, but I guess it could be. Neck rot I believe happens in storage rather than the soil? Correct me if I’m wrong. I cannot see any fungal growths either. Could it be onion eelworm? So far I have pulled 3 bulbs with the same problem, (although no more sightings of tiny worms) it seems the Setton are most affected than the Red Baron although I’m really not sure if the spongy feel to the growing bulbs of both varieties is something to be concerned about.