This year we finally got rain, I noted that at the top of my garden the wildflower seeds I put out at the right time did germinate, but the plants only reached 2 inches in height due to lack of water penetration - top of the hill, the rain ran off. This is an area I tried to irrigate for corn one year, and tomatoes another, and they produced little and poor fruit. I have been studying a very tiny bit in permaculture, so I ordered 6 yards of garden soil with mushroom compost, and when the May rains were due, and while they were pouring, I got out with my wheel barrow and made horizontal (to the hill) swales to slow the water's downhill movement. Before I did it, my bottom of the hill pear tree had fungus and I had standing water near my garage and in the gravel drive. After the swales, the pear lived and produced much fruit, all of which was stolen by squirrels (except one pear - it was tasty and stolen just before it was ripe).
The garden still got overly wet, I think we got over 20 inches of rain in May, have work to do and can't look it up. But my pear tree living, and not having to water my pines until September means I greatly increased absorption. I am using a pond underlayment that allows water to soak in, and mulch over that, to reduce evaporation from the soil and water theft from weeds. These would all be extremely labor intensive on large gardens, pretty labor intensive here.
But I found a great video - uploaded by a local friend studying permaculture, that describes techniques for large plots of land to increase water absorption.
Video: Busting drought for $10 an acre. Enjoy.
