I recently had both a mame Shimpaku juniper and a shohin Tropical Cherry topple due to high winds. There was no pot or plant damage to the Shimpaku. However, the Tropical Cherry was completely uprooted from its pot (I was planning to repot it anyway and had not secured it to the temporary pot). I swiftly repotted it, securing it to the pot with wire.
This got me thinking about methods for protecting smaller bonsai from sudden gusts of wind and other storms. I found quite a bit of information online so I thought I’d digest most of it here.
For shohin bonsai, there are two ways to protect them from the elements. The first is a common way by using string. The second is a method I found partially on the internet with my own modifications.
The first or string method secures the tree pot the plank it sits on using string (this assumes the tree is on a plant or table that you can tie string under and above). Do this by tying two pieces of string across each side of the pot with the tree stem between the two strands and tying the string in knots under or at the edge of the table/plank. You can also use one piece of string and criss cross it under the table to cross both sides on top. These are pretty common and you can find a number of articles that show different ways of implementing this method as well as the types of knots to use.
The second method is appropriate for small shohin or mame trees. First, you need to find a large bonsai pot or a larger tray that has drainage holes. This sounds easier than it is and it will undoubtedly be more expensive than the string method, but I think the will looks better, retaining a zen quality to the display. (See the image for an example of the type of pot I’m referring to).
The pot is large, over 20″ wide and about 13″ deep with a height of almost 4″. Prepare the pot with screens, then fill the bottom with larger pea sized gravel. On top of that use a good blend of 2mm-3mm Japanese bonsai soil (Akadma & pumic) and mix in a small amount of peat moss and crumbled bark mulch. The bonsai soil will provide good drainage and the peat moss and crumbled bark will help to retain some moisture. Fill the pot with this mixture leaving 3/4″ of before the rim. Now fill in only Japanese bonsai soil on the top leaving about a 1/4″ – 1/2″ lip. Now water the soil well until water seeps through the drainage holes. This will help to eliminate dust in the Akadama and pumic mixture and will moisten it well. Now, place your smaller trees into the pot by sinking them into the soil mixture by a 1/4 of an inch. You can sink them to a greater depth if they are more prone to tipping.
Not all trees can be sunk and secured this way. For example, cascading trees need to be sunk in the corners or up against a side so that the tree can cascade over the side of the larger pot but this isn’t going to work for every cascading tree.
I implemented this on my deck recently and found it was an effective way of securing my small trees and it has the added benefit of looking nice with my existing patio furniture thereby retaining a look that I was striving for.
Good luck and let me know if you have found other ways of securing your bonsai against the elements!