Pea Shingle Grow Bed (with pots on top??)

[zanduh]

I know that there are some on this forum who don't like Peter Chan, but in his most recent video he talks about his success as a nursery in using Pea Shingle (Pea Gravel) as a base grow bed with containers that sit right on top rather than burying the trees.

My question for the folks much smarter than I:
1) Since I can't ground grow would I actually get benefit building a raised grow bed and filling it with gravel (very cheap) and then placing training pots on top of that gravel?
2) To complicate it further, would a pond basket make it so that I would have a good ball of fine roots and then a few giant roots that escape the basket (which I would cut away later)?
3) Why does Pea Shingle work well for this application and what are the issues with using it in a bonsai substrate?

 

[sorce]

I worked at a concrete place once, stuff grows right well in pea gravel, see ball bearing principle.

So there is something to it. But like everything else, it has it's downfalls.

What if I said ground growing was for fools?

I mean, a blind man shouldn't wish to be a cab driver.

If you can't do it, and don't even need to, why consider weaker alternatives?

I don't like the idea of some random few escape roots getting large, which will happen.
You certainly have little control with this method.

Stick with pond baskets alone, cut few roots as per sir Pall, and you'll have a root system good enough to get "ground growth" without the ground. And without the need to jack giant roots and graft smaller ones and blah blah blah.

The ground is not really a good idea. Ever.

Sorce

 

[BrianBay9]

I used to keep my freshly collected Ponderosa and Lodgepole pines in boxes buried in pea gravel in raised beds for the first couple of years after collection. Worked great!

 

[Shibui]

You would need to be able to keep the water up to the gravel bed. Gravel only holds moisture between the particles. Most drains straight through and more evaporates. Good air levels make it great for roots so gravel is a good substrate if the water and nutrient is available.
Downside of pea gravel is that it is hard on cutting tools and makes it difficult to cut through the root ball.
Pond baskets and colanders allow roots to grow through into the gravel so growth is faster. The mesh of the baskets should limit how big escaped roots grow. When they get too thick sap flow is constricted by the mesh and the root will slow or die then new ones repeat the cycle. Personally regular root pruning gives better results more consistently and I would also try planting direct into the gravel sans baskets.

 

[MrWunderful]

If you can build a grow bed, then build one and just fill with soil.