We are often asked to help out repotting Bonsai, for enthusiasts new to the ‘sport;’ one of the main questions is how long before I get results?
Well to be honest, it does vary what precise species is being repotted. As an example I will show you an image that I took this afternoon of one of my Maple’s. Just over four weeks ago, I removed around 60% of the existing root-ball and ended up virtually bare rooting the tree as I needed to clear out dead and decaying roots; this was caused by the intense freezing weather during December. It was indeed overdue by twelve months, but the new pot was smaller and shallower; hence substantial removal was required.
Post repotting care is essential for many species, and with this Maple I make it no exception to treat it very gently. It has been kept out of winds, away from frost etc, but I have given the tree several hours of dappled sunshine each day (when the sun decided to turn up that is).
No feed but constant misting; always at night and first thing in the morning then twice a day there on in. I have also been pinching out with tweezers all new growth once one pair of leaves had set. I use tweezers as this helps keep internode length short, (the branch that grows in-between each pair of leaves). It needs to be done quickly as you see it emerging; if the internode is there and the leaves have opened it is already too late!
So …. when I repotted, buds were swelling but not formed, and I very much want slow growth to give the roots a chance to form. It is important when repotting to take the strain away from the roots as much as possible; you are also feeding the roots with moisture. Two-way traffic, always remember that. What goes on the leaf will go down, and what goes in the pot will go up … once new fibrous feeder roots have grown.
Thankfully for the first three weeks response was nice and slow. Then from nowhere the entire leaf formation opened.
Today I have pinched out further new growth; the following image was taken in the garden during a spell of hardening off.
This Bonsai is 34cm tall. I will be reducing the lower branches later on as well as defining the centre and crown further.
The following image is from May 2012 (current.) The tree has been repotted annually, and will likely continue to be repotted each year. This is just prior to a general thin back. Soil medium is completely inert. Feeding is by liquid added to water.