Joanie

I began repotting some trees that I purchased last week, particularly maples. Although a few of them were leafed out, the rest were still just beginning to move.

The soil that they were in was incredibly rocky. What looked like smooth, small gravel used to mulch the top was pretty well the entire content of the soil! There were layers (yes, layers) of a soft red volcanic rock in the bottom, but no organics to speak of. Getting the rocks out of the roots was very difficult. Although it isn't a good time to prune roots if the tree has budded out, I went ahead on the trident because there was no way to get into the root mass otherwise.

On the opposite end, one little tree in a 4" pot that I bought at shohin needed repotting. It's a leather-leaf trident, and I only intended to slip it into a larger pot. However, pulling it out, it was apparent that the soil was pure clay with chunks of red rocks. That clay just washed away, but I was surprised that it was so fine (and then just big rocks) and there were no soil ingredients that were between pinhead sized to small pebble sized! Yet the tree was doing all right, somehow. It will sure do better now, in the new mix!

The ume got repotted too. The roots were also full of rocks, gravel, and pebbles. Very little organic. It would never have survived in our climate, where a hot dry summer day can suck the moisture right out of tender leaves. It's much happier now, in a mix of 60% inorganic, 40% organic. The inorganic is primarily perlite, with some pumice and lava thrown in. The organic is composted mulch which doesn't include peat, but has fir bark as it's primary ingredient. (Along with bat guano) The mix is chunky and light, doesn't stick together when squeezed, and will hold enough water to get the roots through a dry California day.

Soil is definitely one of the most overlooked, misunderstood segments of bonsai art. Yet it is crucial to the health of the tree.

Just had to rant.

Joanie

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