Raised bed layout wrt contour

Howdy,

I’m on a homestead in the San Juans of Washington trying—among other things—to grow storage/staple crops for local consumption. Corn, beans, squash, onions, potatoes are the big ones. We are in Zone 8, with 23 inches annual rainfall almost all of it in the winter and spring. According to the USDA soil map the soil is clallam gravelly loam—supposedly prime farmland with irrigation.

To avoid overtaxing the single source aquifer, we will not use irrigation at present. (A rainwater system is in the works).

There isn’t much slope (<8%) and I’m wondering what the best orientation with respect to contour would be for raised beds. I’m thinking about setting everything up just slightly pointing downhill to prevent pooling and constant mud, but how many degrees? Any better ideas? Also, would swales help take full advantage of what little rain falls in the summer, or is there a better option?

The labor is done by hand so tractor access once the beds are established isn’t an issue.

Howdy Adam, have you seen these videos? Might answer a few questions for you.

Adam, have you not been getting these early fall thunder deluges in your area? I ask because though I am not far away I get far more rain than that so I would not put in swales because I am afraid they would turn into mud pits. How much topsoil do you have? The San Juans where pretty scrapped over by glaciers. As to orienting beds with contour I would also take into account the angle of the sun vs contour.

I'm watching Miles video on water harvesting in dry land with keyline design which seems helpful indeed - and it comes in more than four parts in which the presenter jumps back an forth between micro and macro. All 3 videos I've seen so far have been worth watching if you have a stable supply of electricity. The Ausie starts with a demo of 'the mississippi delta' in sand on the beach, and go into more detail from there - worth watching