At Blooms John Innings No1 is £15 for 5 just thought I would let you all know
Bought mine now for sweetpeas and seeds in the spring
Is this year's compost alright for next year ? I know you are not supposed to use left over compost the next season but perhaps unopened compost will be alright.
There's no reason to not use old (unused) compost. However, if the bags are left outside, the rain can wash-out a lot of the nutrients. In that case you could simply add some fertiliser (eg fish, blood and bone) when using it for planting.
If you're using it as seed compost it won't need any fertilister adding, even if it's been out in the rain all winter.