Retaining Moisture.

Kirk, you need to add as much organic matter as you can.

Composted manure would be good, also home-made compost if you have it.

Going to leave the compost out of it, have some of my own but over the years I added used compost from whatever I grew in containers. The general soil has certainly improved. Originally when "dry" you couldn't get a fork or spade into it at all. I can now happily dig all the way down with just a hand trowel.

Over time more or less everything has gone in - with the exception of much manure. Think I was too concerned on getting the soil more manageable.

Had a quick look outside and I will add another 4 inches to the height, then I think I will partition the bed (3) and start adding manure section by section. Would do all in one but I always seem to have something in, presently leeks and have just bought some overwintering onion seed to go in.

Plan is:
Raise bed by 4 inches,
Section into 3 - Leeks, Onions, Empty.
Add 3-5 bags to the empty bit - biggest bit.
Later add 3 bags to the leek bit - when the leeks come out, later still 2 bags to the onion bit.

Onion section has had a bag added 3 days ago in preparation anyway.

Hoping that should add a few inches extra in depth. Also going to have a talk with the worms about getting it all moved round.

The last 2 seasons I've started using the One Straw method of mulching. Basically you chop everything (weeds, old leaves, green manures) up and just drop it on the soil.

It is tremendously good at soil improvement, very fast & very easy