Dave Joyce says in the book The Art of Natural Bonsai, pg 28, not to feed repotted plants for at least six weeks. Does this sound right? No fertilizer for 6 weeks? I'm about to repot my new young Parsoni Juniper and wondered if I should not apply any food to this new plant for this long? Any help appreciated.
And HI all, I'm new to this forum as well as Bonsai!

Bob

Some say you should never feed repotted trees within a number of weeks, as it will damage the roots.
Others say you sould feed repotted trees, as the roots need nutrients to recover.
(I'm assuming you mean repotting including work on the roots, not simply overpotting a tree, in which case this is not applicable)

I do not feed my repotted trees - simply because it's still too cold outside.
If it was warm enough, I would have fed them. However, I would not use chemical fertilizer, but organic only.

Thanks Auk for the reply.

Yes, I plan to clean up the roots, rake them loose, and remove the old nursery soil before I place the plant in its new home.

Later on in the book he explains a little more. He says the roots of a repotted plant are weak and not yet functioning properly. There is a danger of plasmolysis which is when the normal process of water being drawn from the soil by the roots actually reverses. This is because the salt or mineral concentration of an overfed soil can be greater than the minerals in the roots themselves, which makes the water get drawn out of the plant toward the soil.

I think I will not feed fertilizer after I repot for a number of weeks. I'm sure it will need plenty of water though.

Baron,

This is a risk negligable if you use modern substrate and proper watering techniques (So: Open coarse grained substrate, and when watering, you water untill the water runs from the bottom of the pot).

Much better reason is that if the roots have been trimmed, there are no active roottips. And only the actively growing root tips (The white ends) have roothairs, which enable uptake of nutrients. So you are waisting fertiliser by watering when recently repotted. As you cannot tell at which point new roottips have formed, I, like auk, also opt for fertilizing based on weather, not based on repotting status.

Thanks leatherback.

So if I don't cut any of the roots but just clean them up removing old soil, then the danger is minimal? Because I don't think I'll be cutting roots as I wouldn't know what to cut.

And that is something I have to yet to buy - coarse grained grit. The nursery didn't give me any of that, just starter soil.

All these things I'm learning - keeps giving me pause before I move the plant over...

Bob