Onion white rot is the cause of sometimes a complete loss of an onion crop. The onions grow well but towards the end of the season they start to look rather pale and poorly, when you go to lift you find all the roots have rotted and most times there is a white mould visible on the base.The spores from that crop remain in the ground until another allium crop is planted then they attack the new crop. Up to now there has been very little that can be done to overcome this since they took Armillatox away, but now several have tried using a garlic solution on the soil immediately after lifting before the spores go dormant. This has the effect of getting the spores to germinate but as there is now crop for them to infect and live on the spores die out. I am trying this on my plot where a had an infected crop last year. This picture taken in January shows my autumn planted onion sets 2 weeks ago and I will try and follow them through the season.
The next picture taken on May 4th shows little change due to the long cold spring but they still look
I must now admit that the garlic treatment does not seem to have been effective as the plants are looking very sick indeed ,I have recently read that you need to treat the ground twice so maybe that is where I went wrong. I think later after I have cleared this crop I may try garlic powder and only plant a few sets just to try next spring. If anyone reading this blog has a comment about garlic I would be pleased to hear from them.