Using green manure...

I do. I let is self-seed just everywhere, and I only cut it down if I need the room for a crop.

btw, I never dig it in. I don't dig at all, unless it's to remove spuds or couch grass. Just chop it up and drop it on the surface

Green manure debate...

Thank you for that! It's supposed to be good for attracting pollinating insects, too, so we might just be on to something here with this. Wouldn't the nutrients get down into the soil in more potent way though if they were actually dug in? Would they be better getting in there whilst still green to allow them to break down in the soil than by allowing them to wither and dry up on the surface?

No. The goodness doesn't evaporate, and the worms will drag them into the soil very quickly.

You can't have both. For adding nutrient to the soil, you need to cut the plants just before they flower.
If you want flowers, and they are brilliant for bees, then just leave a small patch to flower

No.
Digging destroys soil structure, it collapses worm tunnels and compacts the soil (you get some air in while you dig, but the soil settles and collapses on itself).

Plants can't take nutrients straight from the plants anyway: they only take soluble nutrient (which is why "quick fix" nitrogen, for example, is in liquid form).
The green manures need to break down into component elements for the plants to take them up. They need to be partially rotted for worms to be able to eat them. Worms don't like food being "dug in": if you watch a worm farm, you'll see clearly that they pull the food down from the soil surface and pull it into their burrows.

The worms chew up the rotting leaves, and poop it out. Then it becomes soluble and the plants can take up the nutrient.

Burying isn't as fast as composting. Most composting organisms (bacteria, fungi, small creatures) live on or near the surface of the soil, not deep within it. Effective composting needs oxygen, as we know. There is more oxygen above the soil than within it.

Try an experiment: put some leaves in a compost heap, and some just chopped and dropped on the soil surface. After a month, see what's disappeared first: the surface mulch or the compost. Compost in heaps takes months & months & months to work. Composting "on the soil surface" is very much quicker.

Look at how a forest works: the leaves fall in autumn. The leaves are gone by spring. Nobody has dug anything in. Stuff grows. Trees fruit. Nobody has been digging, except the worms.



http://organicallotment.typepad.com/...tment/compost/

http://www.backyardecosystem.com/org...ouble-digging/