Somerset,
United Kingdom 
Hello My question is. Over the summer months we have made up some liquid comfrey, now we find that there are several containers over. Will it be ok to store this in plastic containers over the winter months and use again next year? Or should we discard this and start again next year? Will await answer, thank you.
Janice & David Reynolds
4 Nov, 2015
Answers
I think it might smell pretty rank by next year though.
4 Nov, 2015
Thank you for comments - much appreciated. As a novice gardener I will probably be asking for lots of advice from members. Thanks again.
4 Nov, 2015
Comfrey is mostly for potassium/potash feed. I can see no reason not to keep and use. The nitrogen content might reduce as ammonia could be released by micro-organism activity, so I would keep it sealed. It may fill with fungal mats but these are harmless to plants.
Seaweed feed had a shelf-life of years but I think that is pasteurised.
4 Nov, 2015