United Kingdom 
Is it preferable to have air freely available to the process of decomposition of garden waste? Seems to me the closed composting bins that have a tight fitting lid take longer to decompose than the open bin? Many thanks.
16 Mar, 2011
Answers
I think the idea of a compost bin being air tight is to create heat which hastens up the decomposition process! I buy the decomposter granuels water when looking dry and stir regularly.
16 Mar, 2011
The idea is to have it close enough to hold in moisture and heat, but open enough to let in air. Any compost bin with a solid lid needs to have slits or holes in the side to let in oxygen. Stirring also helps let in more air, but the hosepipe probably isnt often needed in the UK--as opposed to here in the desert! : )
17 Mar, 2011
It helps if you aerate it yourself by turning it regularly - you can buy special compost stirrers for use in compost bins. Any heap, exposed or not, which is turned regularly produces usable compost much sooner than if left as an anaerobic heap.
16 Mar, 2011