Part I of Care Instructions for Chinese elm Bonsai dealt primarily with the watering, and healthy levels of sunlight, for your Chinese elm bonsai. In this installment of my report on caring for your bonsai we are going to look at when and how to re-pot, root-prune, and branch-prune your Chinese elm bonsai.

The Proper Time and Methods to Prune Your Chinese Elm Bonsai Tree

Common sense could tell you that the optimum time to prune any tree is when it's in it's top health. This really is true of the Chinese elm bonsai as well, and the best time is in springtime or early summer. It is important to keep up with trimming when the elm is growing rather quickly at this time of year. It doesn't take very long for the Chinese elm to develop good branch ramification. After 4 to 5 sets of leaves have grown out on a new shoot, cut the shoot back to the initial 1 or 2 sets that will be nearest the branch or trunk of the tree. How often you prune will depend on how quickly your tree grows and when it begins to appear out-of-shape. You'll need to strike a delicate balance between pruning too much from your tree so that it will damage it, and cutting enough off that it maintains a nice-looking shape. Valuable experience will help you make that judgment. Vitality is maintained using this method as this technique is then done again throughout the growing season.

Re-Potting Your Chinese Elm Bonsai Tree

Frequency of re-potting is determined by the size and age of the tree, the condition of the roots, and various other factors. Generally if the plant is young, say less than five years old, then you certainly will need to re-pot it each year. If the tree is 5 years old or older then it really just needs to be re-potted every 2-3 years. Repotting is definitely an essential procedure which often calls for root pruning, and must be done properly. The perfect time of year to re-pot and root-prune your Chinese elm is in the early spring. It is advisable to re-pot a month ahead of or a month after you have pruned the tree. The main reason this is very important is that the tree should be able to get through the re-potting process with as little shock as possible.

Root Pruning

Plants roots will always be trying to find new nutrient and water-rich soil. Bonsai trees require new root growth as new root development would mean greater nutrient absorption and greater health altogether. The best time of year to do aggressive root pruning is the winter or very early spring when the tree is inactive.

Root pruning will require the loss of the larger sized roots in favor of the smaller ones.

Get started by gently taking your bonsai tree out of its pot. After the plant has been removed you must divide each of the roots from each other.

After the roots have been separated you may shorten the plants storage roots and remove any remaining part of the plant's tap root. Try to preserve as many of the fine roots as you possibly can. You don't want to need to fold any of the plants roots in an effort to make them fit when you place the root ball back in the pot so trim them accordingly. To be on the safe side do not remove more than one-half of the roots, particularly if root pruning is being done during the dormant season.

When you have completed pruning you can re-pot the Chinese elm bonsai tree by placing the pruned root ball on top of the fresh soil in the pot, adding more soil between the roots. You want to make certain that you have not left any voids among the roots, and they have been completely filled with soil. This can be done using a blunt pencil or a chopstick. After all the empty spaces have been filled up, and the soil tamped down, you'll be able to give your bonsai a drink of water. Go ahead and saturate the soil entirely on this first watering following the re-potting and root pruning. After saturating the soil let it drain completely, and then water it again. This will help settle the soil surrounding the roots.

Keep away from intense direct sunlight for 2 or 3 weeks until the roots have had a chance to recuperate, and don't fertilize for three to four weeks after the roots have been pruned in order to avoid any potential root-burn.