Let me start with the disclaimer: The following is something that is done with Japanese Black Pine. This is my first attempt at cutting the tap root off of a seedling. I saw this on bonsaitonight.com and in Bonsai Today issue 20. These are Cedar of lebanon. They have been growing them for approximately 8 weeks. I don't know if this technique is appropriate for this species, but I thought what the hey, let's go for it. The reason that the tap root will be removed is to stop the root from growing super long as this will lead to the root coiling around the pot. Tap roots are anchors for the tree. They grow deep and thick so that the tree can grow big and tall. However, since these seedlings will live in a pot we do not want a long tap root. After the roots are removed what will hopefully happen is that the new roots will grow in a radial pattern and develop into radial "nebari". What does nebari mean? I looked it up and it literally means stickiness. In Japanese words meaning change according to context. So, here in the realm of bonsai nebari refers to the thick roots that pop out of the surface like an old tree. After I sever the tap root it will be dipped in rooting hormone. Then, they will be placed in 2x2 plastic pots where they will all survive and grow to be exceptional bonsai with the greatest nebari ever. Scenario two, I'll be happy if half of them survive the tap root ectomy.
First thing first I used coarse organic material to plug up the holes in the bottom. The layer was deep enough to just cover the holes. I use organic material to retain moisture. Here in sunny dry southern California I need to battle evaporation. This is especially true with these tiny pots as they do not hold much water. It's early February and the weather forecast for this weekend is for the low 80's F. I do not know if I will have time to water these plants three times a day.
In the middle I placed one of my wife's lipsticks. Then a 60/40 mix of organic material and sand was added around the lipstick. I did not pat the dirt down. Its loosey goosey.
This is what it looks like after the lipstick is removed. The mix was moist so it held its shape very well.
I added some fine sand made from shells and other invertebrates. I used this sand because I couldn't find river sand. I found a 5lbs. bag of this particular sand at a local pet shop. The sand is made of crushed shells and other things. I guess i should have bothered to read the label. The material is very light.
This is what it looked like after all the pots were filled.
The spray bottle is to keep the sand sticky so that a hole can be punched through the middle.
This is a small paint brush. It is the perfect thickness for the cedar of lebanon. I pressed it down the middle about half way.
This is the rooting hormone. After the tap roots are cut off the seedlings will be dipped in this.
I still had time to change my mind and pot the seedling. If you notice the root which i believe is the bit after the white spot about halfway down the plant is very long.
No guts no glory. Razor blades would have been better I suppose. I used some shears to sever the root.
A dip in the rooting hormone. Then the excess powder was blown off.
the seedling is placed in the hole. then the pot is watered again so that the sand closes around the stem.
The seedlings are placed outside in a shady area. It is important to keep them out of the wind also. Now it is a waiting game. When will the new roots start growing?