Hello, Dorothy!
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PS: I hope my poor English isn't so much of a problem....
Nothing wrong with your English, dear.
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Does bare rooting have any risk for the tree?
Yes, depending on the species and the health/vigor of the tree, it can definetly be risky to bare root.
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Does this depend on species?
Absolutely. In Florida we have 2 kind of trees. Ficus and non-Ficus. Most ficus trees can be barerooted without any problems. So can Bougainvillea, Seagrape, Raintrees, Buttonwood and many other species. It really depends on the species, the status of the tree and the
time of the year.
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Why did you choose to bare root and not just reduce the rootball as a whole?
I treat
every tree in my backyard slightly different when it comes to repotting, watering habits, fertilizing and general exposure. This particular Ficus should have already been transplanted a year ago.
I had to bare root it in order to detangle the roots. I use(d) the water hose to clean the main rootball from soil (top and bottom). During this process I also trim long roots and place the tree on a turntable to comb out the remaining roots. With Ficus you want to treat every single root individually. Anything crossing close to the trunk needs to go. Yes, it may eventually melt into the buttress, but you will still be able to see it depending on how big the root is. Also, very often Ficus will grow roots on different plains or levels radiating out of the main trunk. Some of these may have to be pruned or corrected. There are just so many issues that require a bare rooted tree, in order to realize problems while they occur or before they occur.
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Do you let the tree get rootbound before repotting?
To a certain point, yes. With fast growing species like Ficus, you want to avoid "knuckling" roots, roots that are forced to make a harsh turn in order to grow, or roots that are are growing downwards due to lack of forward space. There are other varieties like Buttonwood that like to be slightly potbound prior to repotting. But then again, it depends on what you are trying to achieve. If a tree - any tree- is very old and fully developed, there are means of keeping the growth under control while ensuring the tree's health. I am sure you have thought about that already. A packed rootball is one of the ways..
Hope I was able to answer your questions. If not, let me know.
Best,
Dorothy