Wondering if anyone has any suggestions for techniques / products relating to root restriction for trees in order to maintain a relatively small size. Containers/appropriate cultivars seem the most obvious answer but are there varying types or techniques that are preferable to use in this case?
Too much work for too little gain, I suspect, for techniques to have been developed. Pruning roots is done with bonsai, though.
@kalliwally good afternoon, just seen this and would just like to say that I root prune my potted maples every two to three years. This ensures that I can give a fresh medium and keep these trees in my collection at a manageable size. I carry this procedure out at the end of Winter and just before the buds are going to break. Usually around end of February to the beginning of March. Now your area maybe a little later in Vancouver. Hope this is of help.
Vertrees wrote in his Japanese Maples book about need for routine top pruning of specimens growing in ground when a collection is present, not wanted to take up a large area.
Agreed top pruning also necessary and I do this in early March in the UK and also in June / July to keep branching under control of excessive whippy growth that becomes a problem.
Google root pruning apple trees. This is a suggested method to reduce water sprouts. Depending on the size you want to keep the top, you prune either once or twice a year. Usual implement is a weighted coulter wheel that sinks 6-10 inches in the soil and cuts the roots much like a really big pizza cutter.
