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262 points gnabgib | 3 comments | | HN request time: 0.84s | source
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ralusek ◴[] No.43744184[source]
I'm a gardening and landscaping enjoyer, but I am constantly confused about the bordering magical thinking surrounding dirt, among other aspects of growing things.

If you look at hydroponics/aeroponics, plants basically need water, light, and fertilizer (N (nitrogen) P (phosphorous) K (potassium), and a few trace minerals). It can be the most synthetic process you've ever seen, and the plants will grow amazingly well.

The other elements regarding soil health, etc, would be much better framed in another way, rather than as directly necessary for plant health. The benefits of maintaining a nice living soil is that it makes the environment self-sustaining. You could just dump synthetic fertilizer on the plant, with some soil additives to help retain the right amount of drainage/retention, and it would do completely fine. But without constant optimal inputs, the plants would die.

If you cultivate a nice soil, such that the plants own/surrounding detritus can be broken down effectively, such that the nutrients in the natural processes can be broken down and made available to the plant, and the otherwise nonoptimal soil texture characteristics could be brought to some positive characteristics by those same processes, then you can theoretically arrive at a point that requires very few additional inputs.

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1. hinkley ◴[] No.43745686[source]
The reason chemical fertilizers work is because they provide minerals that a plant might normally trade sugars to fungi to get. So those sugars stay in the plant making larger fruits, nuts, or legumes.

But the problem is you also get water and early/late season sugars exchanged between plants (Simard et al).

So within a generation the soil structure has collapsed, you’re at the whim of every microdrought, and you’re dealing with the Red Queen problem. But like drugs, at first it feels amazing.

> dirt

Dirt isn’t much better than hydroponics. Soil is. Conventional farming has been described by some as “hydroponics in dirt”. That’s why it’s so fertilizer dependent, just like hydro.

There are a few places in the world where there is insufficient phosphorous in the native rock to grow plants without fertilizer. But everywhere else, healthy soil fungi could mine it out of the sand in the soils. If they were left to grow instead of burned to death with herbicides and fertilizers.

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2. goeiedaggoeie ◴[] No.43745835[source]
great post. I posted in this thread above about using a Lomi to convert our organic waste into organic fertilizer (along with a worm farm), a and cultivating nitrogin fixing bacteria with our outdoor fish pond and a flood and drain system. Soil is great to grow in, if you treat it well.
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3. hinkley ◴[] No.43745899[source]
I will say that my only problem with Simard is that she anthropomorphizes the fungi and the behaviors she documented could just as easily be explained by osmotic pressure. Chemicals in a solution of water have “fairness” built into them. The broker doesn’t need to have a strategy for exchange, just siphon off a finder’s fee for making the introductions. The magic is low friction channels that can move solutions over a long (for a single celled organism) distance. That’s magic enough for any kingdom of life.

Sugary sap? Water will enter and sugars flow out. High nitrogen content? Same same.