At work I received a "mallsai" (mass produced bonsai from a mall). The ones with the rocks glued to the top of the soil. It was a nice looking mini-jade. It is putting out new growth, but it is also dropping a lot of healthy leaves so today I decided to repot it and see if it helps with the leaf drop.
I took it out of the pot and noticed it was mixed in with a black soil and woodchip combo. The roots weren't quite potbound and there wasn't any kind of odor or visible issues.
I decided to also test a theory I've been reading on several bonsai sites that you don't need to use any organic matter in your soil as long as adequate fertilizer is used. I decided to make this part of the project. I planted the bonsai in about 70% perlite and 20% sand. I mixed in time release fertilizer pellets in the "soil".
I didn't need to do any root pruning as most of the roots were already feeder roots and there was enough margin between the root ball and the pot edges. I placed a small mound of my soil in the center and placed the bonsai on top. After, I worked the soil in between the roots by working the end of my root rake in between them.
Last, I watered it in and placed the bonsai on the back patio where wind and rain wouldn't disturb it. The picture at the top of the post is how it ended up. I am going to get some decorative gravel or something to top the soil with.
Comments are welcome :)
Saturday, June 30, 2007
Friday, June 29, 2007
The best bonsai soils should both retain water and let excess water drain through it. Additionally, it should resist compacting. This will allow it to stay aerated which will keep the roots healthier.
Inorganic soils are preferred because they have all these qualities. Considered the best in this category, akadama soil, baked clay, is imported from Japan and can be found at certain bonsai suppliers. That is not to say it is your only option. Other types of fired clay soils may work, but akadama is considered the standard. Some people even use clay kitty litter.
Thursday, June 28, 2007
Generally bonsai need to be repotted and root pruned every 1-5 years. Fast growing and younger bonsai are closer to 1 year whereas older bonsai are closer to 5 years. You should carefully lift the bonsai out of its pot yearly to inspect the roots to see if it has become pot or root bound. This means that the root system has nowhere else to go. You will notice the root ball encircling the pot and possibly also coming out the drainage holes. That is a good indication you need to root prune.
Pruning the roots allows your bonsai to develop finer feeder roots. This allows them to more efficiently absorb nutrients from the soil. If you don't root prune it will be harder for water to soak into the soil. Additionally, when the roots can't grow anymore the bonsai will begin to show signs of stress and may eventually die. Trees in the wild are used to making new feeder roots every spring. Similarly, if you root prune your bonsai you should do it in the spring. This is when the tree is ready to regrow the roots you cut back.
How to repot
1) Root rake
2) Sharp dedicated scissors
3) Chopstick or pencil
Once you gently remove the bonsai from the pot you scrub the walls of the pot. Next, start to rake out the roots using a bonsai root rake or chopstick (I like the root rake). This should untangle the roots and free them from the compacted soil. Now, take your scissors that are only used for root trimming and cut all the thicker roots back leaving the finer ones. The goal is to create some space between the remaining roots and the pot wall. Try not to cut more than 20% of the roots away.
Now that the roots are pruned put some fresh soil in the middle of the pot and sit the bonsai on top of that. Try and work the soil between the roots using the chopstick to remove any gaps or spaces. If you plan on wiring the roots (not covered in this article) now is the time to do it. This will help secure the bonsai in place so it doesn't fall over when being moved. Fill the remainder of the pot with soil.
Last, water your tree very well and place it somewhere pleasant where the roots can heal. It won't like being moved around by wind or rain. Also, it is important that the soil doesn't stay very wet while the roots are healing. Do not fertilize your bonsai for awhile after either.
Wednesday, June 27, 2007
Mycorrhiza - the friendly fungus
Not all fungus is bad for your bonsai. Mycorrhiza fungi can form a symbiotic relationship with your bonsai's root system.
Bonsai store excess sugars from photosynthesis in their roots. The mycorrhiza attach to the roots to absorb these sugars, but in return the plant gains the use of the fungi to uptake nutrients from the soil. This is more efficient than if they were to use their roots alone. This is partially because the fungus is so fine that it can get to parts of the soil the roots otherwise couldn't.
It is believed they are especially beneficial to the host (bonsai) in drought conditions and poor soils.
If you repot your bonsai and notice a thin white film between its roots it could be mycorrhiza.
Sometimes it is hard to tell when you should water your bonsai. You don't want the roots sitting in a large amount of water because they could rot, but at the same time you never want the bonsai to completely dry out. There are two low tech methods for figuring out when to water and one high tech one.
Take a chopstick that has no coating on it and stick it in the soil of the pot near the edge. After 15-20 minutes take the chopstick out of the soil and see if it feels damp. If it is damp you don't need to water.
The next time you repot your bonsai take a strand from a string mop and thread it through both drain holes in the pot so that the string hangs out each side. You can tell if it is wet inside the pot if the string still is.
Alternately, for a more scientific approach you can purchase a moisture meter for around $15.00 dollars or so.
Tuesday, June 26, 2007
There are many different materials used in bonsai pots. You can find them made of mica, terra cotta, stoneware, porcelain, wood, and plastic. Most people use mica and plastic pots when their bonsai is in training. If you plan on showing your bonsai you will want to invest in a ceramic stoneware pot. Some people also like terra cotta, but stoneware is fired at a higher temperature which means it is less likely to crack in low temperatures whereas terra cotta may.
Picking the right size
For tall trees:
Pot width = .67*(tree height)
For wide trees:
Pot width = .67*(tree width)
The depth of the pot is generally based on the width of the tree's trunk. A wider trunk should be planted in a deeper pot than a tree with a skinny trunk base. Generally, you should consider getting a larger pot if the trees roots will need to be drastically pruned in order to fit. It is safer to scale into a smaller root ball over time (a few years) instead of drastically doing it at once.
Below is an interesting article I found that I am reposting here. The comments and opinions stated below are from the original author.
Natural Spider Mite MiticideBy Carl L. Rosner
Fill a gallon jug with water and add one (1) or two (2) tablespoons of dishwashing detergent and one (1) tablespoon of vegetable oil (or Neem oil). Shake up the gallon jug to mix the ingredients.
Fill this solution from the gallon bottle into a spray bottle and just before using add 1 to 2 two caps full (from the rubbing alcohol bottle) of rubbing alcohol and spray immediately. If you do not use the full bottle of spray, I suggest the next time you are going to use the soap/alcohol solution add the same amount of rubbing alcohol again, since the alcohol will evaporate. I store this soap/oil solution in the gallon jug for months on end. It does not seem to go bad.
Spray on plants covering all leaf and stem surfaces. You may have to spray from three to four times with intervals of three days. I have eliminated almost any kind of pest that has attacked my trees, including scale.
I do not wash off the spray and have seen no adverse reaction to the trees from this mixture.