severe root triming

[nsellas]

I have root trimed a Japanese hornbeam a year ago The trunk is 3-4". I intend to place this tree in a pot as a large bonsai. It may take years (I don"t care, Im only 69 years old)The top of this tree was cut off aprox 3 years ago and many shoots arise from the trunk. When is the best time to root prune my diameter more. I live in Michigan.

 

[Jay Banks]

I've studied bonsai with a group of pro's and typically they start with smaller material. Say, a trunk diameter of the size of your thumb. But never something larger than 2 inches.

Then they root prune the heck out of it and pot it up and start to train the top growth. Pruning the top periodically keeps the sprouts under control and starts to direct the growth to the form they are trying to achieve.

Bonsai is both an art and a science to develop a healthy small tree.

 

[treetrunk]

Being an avid bonsai enthusiast myself, my advice is leave the tree in a bigger pot for now, contrinue shapeing the crown lightly, and prepare to find the tree a raised sheltered spot in your garden for somewhere to overwinter when the time arrives. Then in early spring just as the buds on the tree are swelling, this is the optimum time to carry out root pruning and repotting. Only remove 30% of the roots and remove the tap root. Any large lateral roots removed could be treated with a rooting hormone to facilitate vigorous rooting. Hope this helps, good luck, and hopefully enjoy your bonsai for many years to come.

 

[John Paul Sanborn]

Your being in MI, you may need to insulate the pot if stored out of doors in winter.