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Club News – December 2020

Happy Holidays!

Parade of Trees Holiday Party 

December 16th @ 7pm via Zoom

The theme of our holiday zoom party will be bonsai decorated for the holiday season using lights, ornaments, etc. The bonsai can be an individual tree, a group planting, a saikei, etc. It doesn’t matter how big or small your tree is. You can also show it live vs. via a photo if you have a setup with good lighting. Consider putting it on a turntable so you can turn it around for multiple views. There’s no limit on how many trees you can do as long as you don’t overdo it. So consider decorating more than one bonsai and/or sharing photos of your bonsai garden. Remember the more members that participate the more fun we will have but you don’t have to decorate anything to attend. So hope there’s a big turnout!

Club members who Zoom in for this event will also have the chance to win a gift-certificate to a local nursery. Richard Phillips will draw the winning numbers and mail the certificates to the winners afterwards. That way you can still win a prize while social distancing. You have to be present at the time of the drawing to win as your Zoom screen name will be your number for the drawing. 

Note that this meeting will not be recorded.

Monthly Tasks

Each month there are a number of tasks you need to do to your bonsai – from repotting, to fertilizing to spraying for pests. We have put together a checklist, customized for the San Francisco Bay Area to help you. This checklist is adapted from earlier work by Mitsuo Umehara. 

This month: December Tasks


Recap of Our September 18 Zoom Meeting

Juan Cruz gave us a fabulous demonstration on how to create a bonsai on a slate slab. Before he got started Juan pointed out that you should always wear goggles and ear plugs when working on the slate. Along with muck for holding the tree in place, you’ll need a some chalk and a hammer to work on the slate.

When picking out your piece of slate, you will want to use a thicker slab if you have a heavier-looking tree. For a less-heavy-looking tree you’ll want to use a thinner slab. Juan prefers to use a thinner slab because it’s not as heavy to move around. He also likes a slab that has some color in it.

Using the chalk, Juan first drew an outline of the shape he wanted on the slab. Remember you don’t want an edge to be in a straight line. Using the hammer he gently tapped along the edge of the slate each time breaking away a small piece of slate. Don’t use a lot of force, i.e., gently tap. And if you need to take off a large section of the slate, remove it in increments tapping along the edge of the slate each time. Otherwise, you could cause the slate to completely crack.

Chalk outline of slab shape
Chalk outline of slab shape
Shaping The Slab
Shaping The Slab

When picking out the slate, look for pieces that have some texture and visual interest. Richard Murray said there’s a 95% waste factor when trying to mine the slate so make good use of your slab of slate.

Once you’re happy with the shape of your slab, use another spare piece of slate and sand along all edges to remove any sharp edges; these can be dangerous. The edges of the slate are not fragile at all. If you have a bump on the underside of the slate, it will prevent the slate from sitting level. Hold a putty knife at a 45 degree angle along the edge of the bump and tap the knife with a hammer to remove the bump.

Next you want to attach the wire that you are going to use to tie down the tree. First prep the slate for epoxy by cleaning it using rubbing alcohol. Make sure you don’t leave any oil from your fingers on the slate.

Juan created three wires each bent in an upside-down “U” shape with a loop on each end flattened like a foot to “stand” on top of the slab (see photo). Each loop will be filled with glue to attach it to the slate. Once attached, the resulting upward loop will be used for threading the wire to hold the tree in place on the slab.

Loop for tie wires
Loop for tie wires
Muck rim to hold soil in place
Muck rim to hold soil in place

Juan used a two-part epoxy by JBWeld which had to be mixed together to start to harden up. It takes about six minutes for the epoxy to harden for use. Then a big clump of epoxy was applied to each “foot” loop. Once applied on the wire, the epoxy will take another 30 minutes to set before you can start tying the tree onto the slab. Be generous with the epoxy.

Juan said you cannot overwater a tree on a slab because you don’t have edges of a pot to restrict it. Surface tension of water holds the water on the slab. You never need to repot a tree on the slab because the tree will be naturally stunted as the roots grow out to the edge of the soil and then die back. Then new roots start growing out toward the edge of the soil. So the root system becomes very healthy and you don’t have to worry about the tree becoming root bound like you do in a pot.

Root ball covered over in muck
Root ball covered over in muck
Moss placed over the muck-covered root ball
Moss placed over the muck-covered root ball

Juan shaped the tree like a Monterey cypress that you would see in the wild that has been wind-influenced by a constant breeze pushing the branches in one direction – not to be confused with wind BLOWN.

Juan only trimmed the sides and bottom of the root ball on the demo tree. Juan says never completely bare root your trees unless it’s an emergency – for example, you accidentally used a bad chemical on it. Otherwise bare root in increments/stages. When you trim on a juniper, cut back to a little branch.

To hold the tree and soil in place on the slab, you need to create a border. Use muck to do that. To create muck, use Akadama fines (1 part) and sphagnum moss (5 parts) torn into tiny pieces, mix together and add water. Keep it in an air tight bag and wait a couple of years before you use it. Check it a couple of times to make sure it is still wet. Sphagnum moss gets broken down over this period of time and acts as a glue to hold it together. Add a little water just before you use it and then knead it and flatten it out for application. Juan first formed a wall of muck around the area on the slab that the tree will be placed within. Next he sprinkled sifted akadama (size small) on the top of the slate before he placed the tree on it. Soil was not needed as he retained the nice soil the tree was planted in.

Juan didn’t put the tie down across the roots but rather along the edges of the roots. That way you don’t see the wire but they catch the roots and hold the tree in place. He then folded the muck up against the roots to hold the soil in place. After that he finished covering all the soil in muck. The roots will grow through the muck and when they hit the air they stop growing. Moss was then applied over the entire mound of muck. When the moss starts to dry out slightly, you know it is time to water the tree.

Moss can be commonly found in shaded concrete type environments that are moist because the concrete is very alkaline. You can also grow moss in akadama fines using alkaline water and fertilizer. Juan likes to use a fish fertilizer called “Alaska” that is available at Home Depot.

Juan plants bamboo groupings on slabs because bamboo can easily break a pot. Juan said that the slab will prevent the tree from getting as cold as it would in a pot but it should be kept out of freezing temperatures to prevent breakage of the slab.

The demo tree was an Itoigawa juniper donated by club member Diane Churchill. Juan wired and styled the tree prior to that evening.

The club thanks Diane for her donation and Juan for all his efforts to make the demonstration such a success. Everyone was truly inspired.

Note that Richard Phillips will be handling the auction of this tree at a date to be determined. So stay tuned for that.


Bonsai Pots – Know What You’re Buying

Since we are having a club auction of bonsai pots, please refer to the article “How to Recognize a Good Bonsai Pot” in our August 2015 newsletter available on the club website. Here you can find out what the blue dot means versus the red dot. For some Japanese bonsai pot history, refer toPaulStephansJapanesePotHistoryPart1

It’s a great presentation. And some fabulous bonsai pots are shown on his website www.kibonsaiart.com

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