In article , MM
writes
My plot was the 'compound' during site development (the one place
where the builders draw off water and electricity). Over the
inevitable builder's rubble the developer laid a load of topsoil,
which has become compacted. There aren't many worms in it! How might I
improve aeration of the soil? I bought a soil aerator yesterday and it
works well, as the ground is very soft after all the rain. But is it
really going to do any good? I read somewhere that forking in some
organic matter could be useful. Would one of the bark-based compost
products be the right thing to use?

Worms will need higher humus levels, so a high humus mulch is the way to
go. Don't fork it in - once the worms arrive (which they will do if you
provide the humus) they will do that for you. Bark based compost is fine
but an expensive way to do it - you should be thinking in terms of a six
inch layer at least. Get hold of anything free that you can - basically
anything with a high content of rotted or partially rotted plant
material. If you can't get anything free, then treat a very small area
where you are planning to plant, and start a compost heap!

You can add almost anything to your compost heap - weeds (let thick
roots dry out first to make sure they're thoroughly dead), vegetable
peelings, soft paper and cardboard, grass cuttings. Go for as big a heap
as you can cope with, as near cube shaped as possible - you want to have
a big volume and a small surface area. You should get something useable
as a mulch in 6 months - this means you could plant now, adding some
bark or coir based compost to the planting holes, and mulch round plants
come the autumn. Keep on mulching over the years and you will see your
soil gradually improve.

You could try the route of complaining to the developer about the
quality of top soil - top soil should have more humus than that.
--
Kay
"Do not insult the crocodile until you have crossed the river"