I think that I'm growing bigger, stronger plants, with more girth to the stems, and since I space them 3 to a slab, they spread outward some, and produce several massive colas each, and are strong enough to hold that weight.

But, other conditions are better now too. And that would cause better plants. But the area of space that the roots have to spread out, allows the plant to grow really well because of that solid base.

And it's easier than cleaning rocks!

HTH

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