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The Importance of Balanced Feeding and Watering

Bonsai, as they are just a small version of regular trees or plants, need food and water just like any other plant. Because they live in a man-made environment rather than in nature, where they would get all the nutrients and water they need through the ground and rain, their living quarters need to be kept in the right condition.

Fertilizing

The purpose of fertilizer is to get the appropriate blend of nutrients into your tree. Fertilizer is made up of N (Nitrogen), P (Phosphorous), and (K) Potassium. The ratios are expressed as 0:10:10 or 12:6:6, in the order NPK. For outdoor bonsai, feed your plant with a higher nitrogen content in the spring, to encourage growth – a 12:6:6 or so. During summertime use a balanced fertilizer like 20:20:20 (which is the same as 10:10:10 and 5:5:5). As autumn comes you will want to begin hardening your tree off for winter with a lower nitrogen level, like 0:10:10.

Each tree is different and it may take a while to adjust to the correct fertilizer level. Signs of over-fertilizing include browning or yellowing leaves, fertilizer accumulating at the top of the soil, and roots that are going black and limp (root burn).

Under-fertilizing can cause equally concerning issues like leaves shriveling up and dieback of branches.

You may have heard of foliar feeding – this is a hotly contested topic, so do plenty of research from a variety of a sources before deciding whether foliar feeding is right for your bonsai.

Watering

Watering your bonsai can seem confusing, but the most important thing is to observe your particular plant – each species is a little different and your climate, the amount of sun, and soil mixture will all influence how quickly or slowly the water is absorbed. The other major factor in watering is drainage – bonsai must have good drainage, in fact some experts even feel that it’s impossible to over-water a tree that has a good drainage system.

When you’re first adjusting to how much water your tree needs, do not set a watering schedule. Instead check the plant every day; when the surface starts to become dry, water thoroughly. Don’t allow the soil to become completely dry. The entire root system needs to be soaked – a good rule of thumb is to water the plant until water begins draining out of the drainage system. Use a fine-hole watering can and water from above the plant. If you can collect rainwater this is even healthier for your bonsai as it does not contain the chemicals that tap water sometimes can.

Under-watering causes leaves and the tips of the branches to begin drying up. The effects of under-watering a bonsai are evident very quickly. Damage from over-watering, on the other hand, can take much longer to show itself. Leaves yellow and fall off the tree and eventually root rot sets in, which may not be discovered until repotting time in the spring.

Pay close attention to your bonsai and follow instructions closely and you will soon get a feel for the healthiest feeding and watering routine for your specific plant.

Bonsai Pests and What to Do About Them

Because bonsai are made from normal plants and trees, they are subject to the same types of bugs and pests as those in your yard and garden. You should monitor your bonsai regularly to make sure that it has not been infested by any of these tiny but destructive forces of nature. They can cause stress and damage to all your hard work and even kill the tree if not caught promptly.

Aphids

Aphids - a bonsai pestSometimes known as plant lice, aphids are one of the most common enemies of bonsai. They appear as green (occasionally black or gray) and can be found under the leaves or on stems. They suck the sap and can spread disease to your plant.

It is possible to remove them by spraying the plant with water, but you can use systemic insecticide if preferred.

Red spider mite

Red Spider MitesThese nearly invisible little pests can destroy a bonsai fast and are hard to see, sometimes making it necessary to shake the plant over a piece of paper. Found more often on indoor bonsai, the mites feed on the tree, causing the leaves to turn yellow and brown.

Spray the bottom side of the leaves with an organic soap mixture or use systemic insecticide such as pesticide pins.

Mealy bugs

MealybugsThese look like tiny balls of cotton on the branches and leaves and frequently gather in clumps. The insects are actually inside the balls, and can cause yellow leaves and slow growth. Not only do they feed on the juices from your bonsai, they also introduce a spectrum of diseases.

Insecticide should be used to rid your bonsai of these pests.

Scale

Scale - common bonsai pestThese insects look like they sound, small scale-like bumps on the leaves, branches, and trunk. A scale infestation will cause wilted, yellowed foliage.

They can be removed manually, as they have a shell that can protect them from chemical insecticides. If there aren’t too many bugs you can brush alcohol onto them to kill them.

Caterpillars

Black Swallowtail Caterpillar feeding on parsleyThese cute little guys can unfortunately wreak a lot of havoc on a bonsai, devouring the leaves. The good thing is they’re easy to see and you can pick them right off.

They tend to come back even when you think you’ve gotten them all so keep checking regularly.

Vine Weevils

Vine WeevilUnlike most pests, vine weevils can cause significant damage to the root system of a plant, because that’s where the larvae feed. While adults are bigger and more noticeable, the larvae are the most destructive and by the time you notice wilted leaves, it may be too late. If you can see adults, remove them by hand and apply a soil pesticide.

The important thing to remember about bonsai pests is that checking your plant regularly can prevent extensive damage. Always check the roots when repotting to make sure there are no unwelcome guests.

Bonsai Soils and their usage

Bonsai soil is a topic that may seem basic, but it can be quite a deep subject. No pun intended.

Quite obviously, bonsai soil is the medium by which the bonsai is provided water, fertilizer and oxygen. In order to do this most effectively, however, it requires varying types and sizes of soils. A bonsai tree requires these different particle sizes and types of soil because it helps them to grow better and emulates the soil the large cousins of the bonsai grow in.

Soil Science 101

Imagine a cross section of the Earth like you see in science books. At the very top, the surface of our planet, there are two levels: bedrock and sediment.

Bedrock is the farthest you can dig with a shovel before you need drills to pierce the rock. On top of that is the sediment layer. This layer is really not that deep comparatively. In some creeks, it’s a mere 2 – 3 feet down. Typically, however, the depth of sediment is 18 – 60 feet deep.

As we look at this layer of sediment, no matter how deep it is, we find that it is made up of various layers of material that increase in size as you go deeper.

On the top layer of sediment, you find silt, which is like powder. This silt most often has organic matter mixed in with it. Going deeper, you find rocks that were once pieces of bedrock. On the top most layers these rocks are pea gravel sized. Then they increase to gravel, then stones, cobbles, then at the very bottom, boulders.

This layering effect is a natural byproduct of gravity. The resettling is a natural result that occurs over thousands of years because the Earth is spinning and going around the sun and water frequently saturates the sediment.

What we find when we look at the large trees is that the root zone is primarily in the mid level of the sediment. This level quite frequently also retains the most moisture as well.

Every time it rains, the water leaches into the soil. As the water percolates down, it draws oxygen into spaces and gaps between the soil particles. The water is held the longest in the mid layer because the top layer is warmed by the sun and blown by the wind, and the bottom layer has mostly larger rocks which don’t hold a lot of water.

Types of Bonsai Soil
Our goal when choosing bonsai soil is to create the same type of environment that the tree would naturally live in out in the wild.

In order to do this, we will need to duplicate the various layers in nature in the bonsai pot. We would just do it on a smaller scale. The top layer particles would be around 1/8 of an inch, the mid soil layer would be ¼ inch sized particles and the bottom layer would be ½ inch and larger pieces.

We can use several different types of soil. Namely, we can use akadama, kanuma, haydite, pumice, grit, gravel, pine bark, peat moss, calcined clay, river sand, top dressings and zeolite.

Basically, these materials comprise types that retain water, types that don’t, and types that do both –they hold some water and they fluff, and aerate the soil.

Akadama

Akadama is the best known, all purpose bonsai soil. The name means “Red ball soil.” It is the volcanic clay that Japan is made of. It holds water very well, but due to larger sized particles, leaves plenty of room for oxygen to get to the roots. Akadama will break down over time into a silt type sediment.

Calcined Clay

Calcined clay is ground up brick. The brick making process ensures the product will never break down. Calcined clay is sometimes preferable to sand because it has larger pieces and screening gives you several different sizes. Calcined clay will hold water somewhat, but it’s purpose is to fluff the soil and make it more porous.

Haydite / Expanded Shale

Haydite, also known as expanded shale, has undergone a firing process that forces it to explode from the inside. This makes it hold some water, yet it mostly makes the soil porous. It can be screened into several different sizes.

Pumice

Pumice is a white volcanic rock which is ideal for bonsai soil mixtures. It holds some water, but chiefly aerates the soil making it more porous.

Grit

Grit is larger pieces of sand that are sharp. Grit opens up the soil and does not hold water.

Kanuma

Kanuma is Japanese soil, like Akadama, but it is slightly acidic. It is used mainly for Azaleas, Camellias, Gardenias and other acid loving Bonsai. Kanuma holds water well and comes in various sizes.

Peat Moss

Peat moss is an organic sphagnum moss that comes from the peat bogs of Canada. This product holds moisture for a long time. This product typically comes in long fibers, but can be broken down into a small powdery material.

Pine Bark Chips

Pine bark is an organic soil amendment that is about 50/50% dual duty. It holds moisture, though not as much as sphagnum moss, and it fluffs the soil, though not as much as haydite, calcined clay, river sands or grit. Since it is organic, it will break down over time.

River Sands

A type of grit that is excellent at opening up the soil to oxygen. It ranges in size from 1/8 inch to ¼ inch, so is best for top and mid layers.

Top Dressings

Mostly used for decorative purposes, top dressings are sands or stones and do not typically have any purpose in bonsai soil other than a purely aesthetic purpose.

Zeolite

Zeolite is similar to Akadama and Kanuma. It is quarried in Japan, and retains moisture and can be screened into multiple sizes for use. Zeolite is more akin to Akadama than Kanuma however, because Zeolite is PH neutral as is Akadama.

Putting the Soil To Use

Some species of plants require a soil that retains more water and others enjoy soils that are more porous and dry. This means that you can use the various soil materials to create specific versions of soil for specific types of plants and specific climates.

The mixtures of soils can vary from heavy moisture retaining, to arid soils. Since Akadama or Zeolite are excellent bases for soil mixes, I suggest using various sizes of these and mixing in percentages of other material depending upon layer and species. Note: If your plant is acid loving, substitute Kanuma for Akadama or Zeolite.

For example, Maples and Beeches thrive in 100% Akadama that has been screened by size. Junipers like 50/50% mixes of Akadama to calcined clay, haydite/expanded shale or grit. Most every other tree falls in between these mixtures.

While it might sound more complicated, most trees, if not all, would thrive using the layered approach found in nature. This means that the soil from bottom to top is made up of several different materials in differing sizes.

Starting with the bottom layer as if potting a plant, add large pieces of akadama, calcined clay, pumice and haydite in pieces ½ inch or larger to the pot. On top of this layer add in ¼ pieces of Akadama, pumice, pine bark chips, and river sand. It is into this layer that you will plant the tree. On top of this, the top layer would consist of 1/8 inch pieces of akadama, pine bark chips, and pumice. To top it all off, you could then apply a top dressing of sand which complements the pot and the tree.

Hopefully you now see that there is a science to soil which takes it out of the realm of mere dirt. As you purchase different materials and spend some quality time with your bonsai, you will start to see how all of these materials can work together for you. Every mixture can be tweaked depending upon the climate your plants live in. If it’s extremely rainy, windy, cloudy, or sunny throughout the growing season, you may need to tweak the soil depending. If you live in Arizona and want to grow bonsai, you are probably going to have to add peat moss to your soil. If you live in Seattle, you are probably going to want to add more pumice, calcined clay or grit.

Three Must Have Bonsai Tools

The bonsai hobby has many specialized tools which make the task of pruning, wiring, planting, watering and other general maintenance of your bonsai trees much easier. That said, there are 3 tools which I believe are must haves and you should definitely purchase these first. These three tools could be your entire collection of tools, or you could expand your tool set over the years.

So what are they? They are the Shear, typically a butterfly shear, a concave cutter, and a chopstick.

The Shear:

Historically, the butterfly shear is used for bonsai, however the bonsai tool manufacturers have made several different types of them. From the larger butterfly shear, to slim long nosed shears, and everything in between, there is a vast selection of shears to choose from – one to suit everyone’s tastes and budget. Speaking of budget, a quality shear will last you a lifetime as long as you take care of it. So buy a good quality shear. The Fujiyama brand shears cover a range of quality, but compared to everything else out there, they are very high quality. The bulk of the line is second only to Masakuni tools. That said, the heavy duty Fujiyama shears are on par with Masakuni tools, but at a significant savings.

The reason the Shear is the number one tool for bonsai is that it is a precision tool and can take out small amounts of material. This helps refine the plant into the desired shape. Because of its ability to be nimble, the shear is the ideal tool to use to get in between small, fine branches and take out a specific twig or leaf set. The shear is the main tool to use on your bonsai.

Taking care of your shear is easy! All you have to do is keep it dry and oil it from time to time. The only real way to ruin a shear, or any bonsai tool for that matter, is to drop it on the pavement, or leave it outside in the rain and elements for an extended period of time. Being steel, they will rust if not taken care of. Taking care of them is as easy as having a dry place for them and running some oil across the blade after each use.

The Concave Cutter:

The concave cutter was designed especially to cut the larger branches that the shear cannot cut. This tool is also used to help shape the bonsai tree, but it is specially designed to cut a small groove into the tree so that when the tree heals, the scar will be minimal.

Have you ever noticed that on trees in the great outdoors when someone cuts a branch off it leaves a scar? Usually that scar sticks out from the tree and it’s obvious that a branch was cut there. The concave cutter is designed to nip into the trunk of the tree so that when it heals, it will heal flush and smooth, thus minimizing the appearance that a branch was removed there. There is no better tool for this task than the concave cutter. Again, you should buy the finest quality you can – Fujiyama brand of course – and take care of it by keeping it clean and dry.

The Chopstick:

When you plant or repot a bonsai tree you will need to firm it into the pot. Also, if you had to prune the roots of your bonsai tree, you would have removed all of the soil around the roots in order to trim them – ideally with your special shear for this purpose. The way you get the soil back in and around the roots is by using a chopstick. Nothing else can do this for you. If you set the plant in, and merely dump the soil over the top and press it in, your tree will either fall over or die because it can’t get any water. You need to work the dirt in between the roots and firm it in with the chopstick. Give it a good press with your hands and then water it in. Also, the chopstick is extremely useful for making the little clips with wire that hold your screens in the holes in the bonsai pot. As with the shear, the chopstick is a versatile tool.

So, obviously, there are a couple other tools and supplies that you will need to completely take care of your bonsai. Bonsai wire comes to mind. But if you wanted to, because bonsai trees grow slowly, you could use only these three tools for many, many years and grow an attractive bonsai tree.

Just remember, when you buy a tool, buy a quality tool like a Fujiyama tool available at Dallas Bonsai Garden. The other tools will bend and break on you and get dull cutting edges after a couple cuts. Why waste your money? If you buy a good tool and take care of it, you won’t have to buy another one ever; unless you wanted to have one for your spouse or child, of course. Compared to every other tool on the market, dollar for dollar, you can’t get a better tool than a Fujiyama tool. So there you have it, the 3 must have tools. Of course you can add to your collection, but if you start with these 3, you will be prepared enough to handle everything you will encounter in the first year or two.

The Rules Of Bonsai

I have thought long and hard about the rules of bonsai. There are rules for almost every aspect of the bonsai. These rules specify what a Bonsai tree is supposed to look like and what can and cannot be done.

For instance:

  • The bonsai can never be placed in the exact center of the pot.
  • The trunk should lean slightly.
  • The trunk should flare at the bottom and the roots should radiate from the flare.
  • Branches should not cross the line of the trunk.
  • Branches should not come toward the viewers viewpoint (foreshortening)
  • The first branch should be one-third up the tree so that the upper two-thirds of the tree have branches and the lower third is bare.
  • The branches should alternate left then right up the tree.
  • The pot should be a certain thickness depending upon the radius of the tree.
  • Etc, etc, etc.

All of these rules! There are a hundred or more. Are the rules accurate? Maybe. Are they necessary? I don’t think so.

When we create a bonsai, what are we trying to do? Follow rules? No. We are trying to make a specimen tree in miniature. Let me say that again. We are trying to make a SPECIMEN tree in miniature!

Unless you live in the desert, I know you have seen couple trees in your lifetime. Have you ever seen a tree that had branches near the base of the tree? I have! Here in Atlanta, Magnolias come to mind. Almost every old Magnolia I see has branches very close to the ground, if not touching the ground. In fact, it would be odd to see a magnolia with one-third of its trunk bare. Lodgepole pines, on the other hand, have long trunks and only have a little vegetation at the very top. I’d estimate that only one-eighth of the top of this type of tree has branches and needles.

Every species of tree has a different look and has different growth characteristics. A dogwood looks different from a cherry and a maple and an oak. There are similarities, but there are also differences. As the French say: Viva la difference!

I have seen some trees that look just like a Japanese painting. Gorgeous! Yet, they look more like topiaries than trees. You see, in my opinion, there is a difference between stylized trees that look like the ancient trees in Japanese paintings and a tree you see in the wild.

Where many people are placing stringent rules upon what a bonsai is and is not, I accept all styles as bonsai. In fact, if I had to place rules on the art, I would only have this statement:

A Bonsai should look like a miniature specimen tree in a pot.

Yes, I know this opens the door too wide for some who are more dedicated to the old ways. But to me, if it doesn’t look like a tree, it’s missing the point.
The hobby of Bonsai is on some level, the living of a fantasy. The goal, is a perfect tree in miniature. Sometimes, perfectly beautiful specimen trees in the wild have branches pointing at you, or branches in the lower third. My suggestion is, do what looks right to you. Forget the rules! You know what a tree looks like. Your bonsai should be your perfect tree. The one you see in your mind. If you are afraid to thin a branch because it goes against a rule, but you know it will look better, my suggestion is to thin the branch.

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