Root networks and diversity in multiple containers

As a believer in the benefits of no-till, diversity and sharing of nutrients between plants, I'm wondering if this can be extended to an urban garden consisting of multiple containers.

If containers are only big enough to each hold one or two plants, then how can we get these benefits? A really simple example would be two containers, one populated by a nitrogen fixing tree and the other containing a fruit tree. If we cut a 10cm/4" diameter hole in each container and connect them with a short soil filled pipe, are we going to get benefits? I assume yes, but anyone got any data or experience on this?

I've got a large flat roof area that is currently home to hundreds of container plants, and I want to maximise the effectiveness of container growing in this location.

I have a few dozen pots and containers. I hardly ever change soil in them.

Most containers have several plants balancing each other. I really don't pay attention to balancing nitrogenfixers etc... So establishing an elaborate contact between pots is perhaps to labor intensive. Why not add plants to your existing pots ? One that works well for me is wild strawberry, others are lemon balm, orange mint, (blood) sorrel. One that does NOT work - it should but really does not is thyme.


My basic soil mix for most of the containers is an enriched peatsoil to which i added sand. In some cases i added limestone or dolomite gravel. Later i further diversified with seashells or silex or shale. In some pots i have added the local sandy loam. Sometimes i apply the rocks or shells as a stone mulch.

At the bottem of most containers i have a silex drainage layer.

Recently - the last 2 years or so - i added powdered lavarock 2 to 3 times each year. More to keep out bugs and slugs than to boost soil fertillity.

I have used this method for years both indoor and outdoors and it seems to work. It seems to work though by all accounts it should not. I grow mostly herbs and strawberries in those pots.  I reckon that by adding rocks of different composition and by keeping a different water balance i help the weathering of the rocks. The plants take what's needed. There are natural fungi in the containers - i have inedible mushrooms in late summer or autumn.


I should add that we have a fairly nitrogenrich precipitation in many parts of Belgium. So that probably helps. That is by the way No Adequate explanation because my first experiments were indoors and with cacti.

Steve Farmer wrote: If containers are only big enough to each hold one or two plants, then how can we get these benefits? A really simple example would be two containers, one populated by a nitrogen fixing tree and the other containing a fruit tree. If we cut a 10cm/4" diameter hole in each container and connect them with a short soil filled pipe, are we going to get benefits? I assume yes, but anyone got any data or experience on this?

I've got a large flat roof area that is currently home to hundreds of container plants, and I want to maximise the effectiveness of container growing in this location.

While it is possible that connecting containers might allow mycelium and bacteria to spread from one to another, the odds of nutrients actually traversing this space are pretty slim.
Nutrients generally travel with the force of gravity (downward, not sideways). The other issue would be the size and actual location of the connector, 6 or 8 inches diameter pipe would be more likely to work than 4 inches diameter.

It seems like a good experiment though, and it would be interesting to see the results of such an experiment.

Redhawk