A few days ago I happily started to give my 5 trunk raft Winterberry or Ilex verticillata 5 trunk raft its yearly springs haircut when I noticed to my horror that many small and some ticker branches had died during last year’s reasonable mild winter?! So I had no other choice than to get him out of its beautiful “Isabelia” pot to look if something was wrong with the roots?! And what I discovered was that a lot of the older soil was not all removed during its last repotting and had become compact and socky underneath the large base! Many other roots that did have room had become long, leggy and without much feeder roots circulated the whole pot!
Below: Jan. 2018. The tree in better times during the yearly “New Years” toast at “DESHIMA” Bonsai centre (NL). I was also very proud that he was selected to shine in the prestigious Noelanders Trophy (B) later that same year!

My handmade “air pruning” plastic pot.
Some months ago I discovered to my surprise that for no apparent reason a lot of the smaller and even some thicker branches had died back on my 5 trunk Winter Berry (Ilex verticillate) raft. So I took it out of its pot and discovered that the very compact rootball had a lot of very strong fleshy long ones growing around the outside and dos smothering the smaller important feeder roots and blocking the holes in the bottom of the pot! I had noticed a few of these long useless thick roots before during an earlier repotting and simply removed them! He was doing just fine back then and showed no ill effects after the removal of those roots?! So to get the tree back to that former so obvious good health I must stop these useless killer roots from coming back! So I decided to make my own special homemade “air pruning pot” for it to grow in for a season or two!
Because, when plants/trees are growing in a pot that allows the air to penetrate through the holes in its walls, like in the makeshift plastic mash pot that I made, then roots will never grow to that length and or thickness. Why do you ask? Because as they grow and reach the bottom and the sides of the pot, they are naturally pruned (dried up) by the air, which forces the plant/tree and Bonsai to sprout new, fresh roots that in turn penetrate deep into the depths of the soil. I had an old open structure plastic food/fruit crate that has just the right sizes! I covered the inside with the famous black gauze we use to cover the holes in our pots with! 1 mm wirers were used to hold it in place. Below: The finished makeshift open-air Bonsai container!

Below: The new air pot and behind it the poor Ilex and in the background two other trees waiting for their turn.

Below: In its new pot just after watering until the water that runs through was clear.

I placed her in a warm and sunny spot and hope that she will recover back to her former health! More repot stories will follow soon!
“DESHIMA” Bonsai Centre: Ir Lelystraat 44 2912 CH Nieuwerkerk aan den IJssel. The Netherlands.
teunisjan@deshimabonsai.nl https://www.deshimabonsai.nl/ https://bonsaishop.nl/