It Happens (That’s a famous saying. Don’t you recognize it?)
The dog’s tail knocked a small pot right off the table. The kids were tearing through the living room and your bonsai tree went crashing to the floor. My personal favorite- the courier company employees decided to play soccer with my carefully, even lovingly boxed bonsai tree on its way to you and you opened the box to find a pot in pieces.
Don’t panic. You can curse a little though. It helps.
Step One- Protect the Roots
If at all possible, keep the tree in the same pot, even if it means that you will bring all your arts and crafts skills and a half a roll of duct tape to the table to do it.
If the pot is a total write off, find another pot and with how ever much soil you can pull together move your bonsai. Watch out for wire. I wire most of the trees I personally work with into the pot, so it you can, grab a pair of wire cutters and look to the underside of the pot to see if there is any wire or if something that you can’t quite explain seems to be holding you bonsai tree in the shattered pot- look for wire and cut it.
Honestly, if you’re scooping your tree off the floor and trying to grab enough soil to shove in another pot, this is not the time to worry too much about technique. Cover the roots. Water the tree. Order a new pot.
How big? We’ll if you’re looking at a repot caused by my buddies at the courier company, don’t worry I’ll send the same size ( you can always ask for a colour - I’ll try to match it) If its a tree you’ve had for a while and needed a repot anyway, you have a choice of the same size or moving up a size.
No problem about being exact, but stay as close as possible to the size you had. Check out a tape measure and estimate how wide your broken pot was at its widest dimension ( assuming a rectangle or oval) Take your best guess at the depth.
Step two - Order a new pot.
I sell pots Here’s a link https://zengardenbonsai.com/collections/bonsai-pots-ceramic-glazed-pots. If the couriers broke it I’ll replace it for free- no need to worry I won’t start to grouse and curse until I’m off the phone. ( But I must admit that the part that really frosts me is that they break the pot and then I get to pay them to deliver a new one. No, they don’t cover damage to ceramics or live plants.)
Enough grousing. You have a tree to save.
Step three - Prep Your Pot
When you’re getting a new pot you will also need new soil and “gravel” to provide an aeration layer on the bottom of the pot. Crushed bricks, large aquarium gravel, pot shards, all this will work. The aeration layer is only deep enough to cover the bottom of the pot and allow air to get to the roots. It also helps that the aeration layer helps prevent the bonsai soil from washing through the drainage holes.
Please- order bonsai soil. Don’t use garden soil or potting soil in a bonsai pot. It holds too much moisture and since the shallow pots lack the gravity pull of a deeper pot to assist with drainage, a poorly draining mix can be the kiss of death. Chances are that any premixed bonsai soil will still be more moisture retentive than a true bonsai soil- which frankly looks like gravel and truly freaks people out with its most unexpected absence of anything that looks like dirt.
I really hope that the pot you get comes with drainage screens and wire threaded through the bottom. If it doesn’t - complain.
Make sure the screens are in place and the wire is threaded. Spread out the wire so it wraps over the sides of the pot. Spread the aeration layer across the bottom of the pot. Cover it with a thin layer of your bonsai soil.
Step four- Place your tree
Make sure that your tree is well watered and carefully remove it from its temporary home and gently remove most, but not necessarily all of the soil. (wooden chop sticks - perfect for this job….and you’ll need them again. You want to plant it so that the soil level is roughly the same as the edge of the pot.
Now, gently spread the roots out. You want to distribute them as evenly as you can. Rest your tree in the pot so that you get a feel for how much extra soil you should add before you permanently place your tree. Add that soil. Snuggle your tree into the soil.
Take the diagonal pieces of wire and being careful not to jam the roots up, twist the wire to hold the tree in place. Trim the ends so you don’t cut yourself of the wires. ( trust me it happens!)
Now you can finish adding the rest of the soil to the pot. Use the chopstick to help work the soil in around the roots. If you push the chopstick into the soil and then pull it back out you’ll see how the soil will fall into the hole.
Leave about a quarter inch of space under the rim of the pot so that when you water it doesn't just run off the side.
Step five. Water your tree and pat yourself on the back!