Dryland Strategies: Swales within Swales

Concave beds in desert climates have had me thinking for a long time about whether here in a desertifying mediterranean cimate.

SO I created a swale within a swale, mini concave planting rows that are concave and trap water. I also have the depth near the depth of the swale path, so when I flood it or when it rains, those crops and seeds are getting watered through capillary action.





I'll post my progress as it goes! So far I can tell that it is retaining moisture well!

Can't see the pictures. What am I doing wrong?

Don't worry Lucia, it's not you. It's possible the links to the photos have broken since the original poster put them up, or maybe there was an error and the photo links were never working. Hopefully Matt will see this and re-post the photos.

Thanks!

Just thinking outloud here, but wouldn't it work better if you just planted inside the swale?

Cheers,
Lucía

That's where you walk. It gets compacted. You don't walk in the soft berm where the plants can put their roots around with ease.

I'm sorry to be so thick, Matt. Are you saying that you walk in the area that gets filled with water? And you plant in the groove between the two small berms?

All good. Explanations without pictures are difficult.

Here's a great video:

Hi Matt, thanks for the video. I do know how swales work but I don't understand your idea of a swale within a swale. Also, I tend to walk on the land above the swale, not the inside of the swale itself. I guess you can if it's full of, say, gravel, or compacted mulch, but in drylands, I tend to think it is better to plant within the swale, YMMV.

I genuinely want to understand your idea because I, too, live in a dry area and I'm always looking for strategies.

Cheers,
Lucía

The swale idea is this: You walk on the path where water collects in large rain events. You want something large enough to take a wheel barrow down & large enough to hold a lot of water.

The Swale within a Swale idea goes further: Make a contoured ditch inside the berm but small, just for plants, then plant will have a hiding space that is shade and retains more moisture. If they just have that shade and that protection, moisture has a huge ability to stay in comparison.

Make sense now?

Yes, it does make sense to provide a microclimate for the seedlings. Here in Madrid, in the wild you can see that most trees grow near large rocks that offer shade and mosture retention in summer, and heat in winter.

Keep us posted about your progress, please.

Cheers,
Lucía

LUCIA!! YES!! In our area, the central valley foothills, has the same effect. Even in the drought, under the live oak and blue oaks, you'd see a halo of green growth.

Matt, I suspect one effect of the stones is to shelter new growth from herbivores. At least here in the mountains near Madrid, where rural areas are hugely overgrazed. Do you think that is a factor where you live?

No, I think it is simply more generalized: a Microclimate effect.

Stones: condensation - rocks condense water on themselves and are 100% runoff, so that is why plants grow so intensely and toughly around them. They also provide shade and protect the tender parts of the plant and roots, so that they can never be grazed down enough to cut into their vigor.

Under Trees: shade, sometimes windbreak if there are enough trees and their branches approach the ground.

Swale within a swale: shade and partial shade at early and late times of day and when surrounding plants are even the same height (since they'll be lower). It also can provide some shelter from the wind though an eikmann spiral no doubt would still be occurring though have only a small effect.

The wind spiral won't affect the plants themselves, but those a little further along.

Thanks for the info on rock-plant groups in your area. One more piece for the puzzle.

Cheers,
Lucía