Helping garden soil retain water
I've followed this forum on and off for a few years, and have tried to put the advice given to work in creating an organic garden. About 3 years ago my family and I started a small raised garden bed -- we initially ordered a few truckloads of a topsoil/compost mix, and have added our own compost since. The initial soil looked great -- a nice dark brown -- but after working with it for the first year we realized that it only looked nice -- in fact it was basically dark sandy sterile soil.
We've added our own compost for two years and have grown two winters of cover crops that we dug into the soil each spring. We actually moved the garden this year to a new spot in our yard, and while digging up the soil to move it we FINALLY noticed earthworms (until this spring it was still relatively sterile soil). Not a lot, but a few here and there.
What I am noticing is how sandy the soil still is, and how it does not retain water. I would have thought by now that we'd have improved the soil quite a bit, but that would not appear to be the case. As a matter of fact, we've had rain for a few days and while our yard is a mucky mess the garden soil is dry and barely clumping.
Is there a point where you have to add clay or something like that? Can anyone offer suggestions as to what I can add to this soil to encourage some clumping and water retention?
Thanks. mcaren (in Va. Beach, VA -- near water, yard has acidic soil although garden is "fabricated" soil...)