Bonsai Development and Growth - By Kelly Watrous
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Bonsai Development
and Growth
By Kelly Watrous
Bonsai Development and Growth By Kelly Watrous
Bonsai Development and Growth
Outline
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Bonsai Development and Growth By Kelly Watrous
Bonsai History
The exact history of Bonsai is unclear, due to the fact that most
of it comes from myths and legends. Most sources tend to favor
the story that bonsai originated during the Han Dynasty (206
BC – 220 AD). The legend says that Han created a beautiful
landscape in his courtyard that he could overlook. In China it
was called Penjing. It became very popular and grew
commercially. Estimates are that the art reached Japan during
the Heian period (794-1191) brought over by Buddhists. Upon
establishment in Japan, the name changed to Bonsai, basically meaning plant in pot.
Bonsai Overview
Bonsai is a very ancient art, a mix of horticulture, art, and nature. It takes many
years to create a bonsai and many meticulous hours of maintenance. There are
certain guidelines, tricks and techniques for
growing bonsai to achieve a very specific
look. Traditionally evergreen trees are used,
however anything grown in a pot can be
considered a bonsai including flowers and
vegetables. Many factors are involved in
the creation of a bonsai including: shape,
height, curves, leaf size, trunk size, branch
spacing, branch direction, and many others.
To achieve the desired look of a bonsai,
many horticultural techniques are required focusing on the roots, branches, and
trunks.
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Bonsai Development and Growth By Kelly Watrous
The Roots
Root pruning is one of the key elements that keep the plants healthy and balanced.
A bonsai’s root system is a very important part of the plant structurally as well as
aesthetically. Roots grow naturally, which is
something that isn’t given a second thought in
nature. However, growing a tree or large plant in a
pot takes some work. Roots will grow quickly and
saturate a container or pot to the point of pushing
the plant out. If the plant is root bound, they dry
out faster, and increase transpiration. Plants will
also have slower, and less growth of branches and leaves, which is the general idea
for bonsai, however not done properly it can lead to a plants decline. To accomplish
keeping the plant small and healthy requires root pruning and repotting periodically.
The beginning of the roots, where they meet the plant is important to the design, it
gives the impression of a strong tree grasping the ground. In this case the plant
should be potted so that parts of the roots are above the soil. The visible roots
should not be snaky, but straight, and should not cross over each other.
There are several factors involved in the decision to prune the roots. The first factor
is the species, then the size of the container, and also the environment. The time of
pruning is also a very important factor. During the fall, even though leaves have
fallen, photosynthesis slowed, and growth has halted, the
roots are still very active moving food around the plant.
Because roots don’t care if it’s light outside, they will
continue to grow especially in the ground where it’s still
warm. To prune roots at this time would cause more root
growth than containing. Until the temperature starts to cool, roots will continue to be
active. Pruning in the spring is the best time because the plant will not suffer any
excess transpiration from the pruning.
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Bonsai Development and Growth By Kelly Watrous
By pruning roots, larger secondary roots are cut and out of the cut end grow many
feeder roots. This creates a much denser root ball. As the roots are pruned
repeatedly the root ball becomes denser and denser. This is beneficial to bonsai
design because of the small pots that are preferred in the design. A dense root ball
of mainly feeder roots can utilize as much soil as unpruned taproot and secondary
root systems.
When pruning the roots, only about 1/3 of the root ball should be removed at a time.
The cut roots should be sprayed with water to prevent the drying out of the tips and
killing the sensitive root hairs. If buying a tree from a nursery, it may take a few
stages to prepare the roots for a transplant into a pot.
Root pruning should be in conjunction with branch pruning. There needs to be a
balance between the roots and branches. If too many of the roots are pruned, the
water and mineral uptake will not be able to provide for all the branches and leaves
to survive. Also, if there are not enough leaves to photosynthesize, there won’t be
enough food to use and store.
The Trunk
The trunk and bark are probably the most important
aesthetic pieces of a bonsai because of the goal to
imitate age. By manipulating the trunk and bark this
can be accomplished. Many young trees aren’t even
planted in pots for a few years to give time for the
trunk to develop. The tree is finally removed from
large pots or the ground after the trunk has reached
the diameter desired. The first cut is up the trunk
one third of the desired total height.
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Bonsai Development and Growth By Kelly Watrous
After the terminal bud is cut off, the plant will start new growth. A new leader should
develop on the top of the cut off trunk. By cutting off the terminal bud and cutting
down the leader, it slows the vascular cambium which in turn slows the diameter
growth of the trunk. The new leader will grow much more tapered than the original
leader. As it gets larger the process of cutting it down again is applied until the
height desired is reached. The new leaders grow more and more tapered because
the lower trunks keep growing while the new leaders are just starting. Cutting the
leader and terminal bud off at an angle will form the curves of the trunk that help the
illusion of age.
Most species of trees have bark that ages and matures with the tree. Sometimes the
color changes and other times the bark becomes furrowed which combined give the
tree a look of age. The trick with bonsai is to try and imitate that with younger trees.
The bark is composed of dead cells. As
new layers of phloem are grown, the older
ones die, forming the bark. The new layers
push the older ones out, causing the bark to
split and peel. A tree that expands slower
and has a somewhat large amount of new
phloem produces more dead bark. Another
factor is the amount of foliage a tree has. If
the tree is growing slowly, but produces a
large amount of foliage it will produce dead bark more rapidly. This could be
because greater amounts of food and sugars work their way up to the foliage
because that’s where the majority of the growth is if other growth is being restricted.
Perhaps that causes more phloem to produce annually and therefore more phloem
to die as well.
A common technique to enhancing the bark is called a “Sphagnum Wrap”. This
targets external factors instead of the harder to control internal factors. Bark matures
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Bonsai Development and Growth By Kelly Watrous
faster when surrounded by vegetation. The reason for that is the vegetation protects
the bark from natural elements. It also slows growth because the tree is competing
for nutrients and water with the vegetation.
In the first step of this process the outermost layer of bark is rubbed off with abrasive
paper. The object is to score a bit of the bark in a few places, but not touch the live
bark. Next, sphagnum moss is used to pack around
the area that was rubbed off. It is loosely packed
around the bark, and tied to hold it in place. For this
process to work, the moss must be kept moist at all
times. This process prevents the drying of the bark
and at the same time permits water to seep into the
bark and into the dead phloem cells. This process
may take as long as two years. In conjunction with
this process, it’s important to remember to keep as
much foliage as possible to keep the phloem turnover large. This technique will
cause the bark to split and furrow at a much faster rate than the natural process.
The Branches
The third major element is the branches and of course the attached foliage. The
branches are one of the last elements focused on during the initial bonsai
development. The only aspect of branches that are really applied in the first few
years is the placement. Otherwise the focus is on developing the trunk and roots.
Like roots, cutting the branches is all about timing. Pruning the branches in the
summer during the time of growth, when the majority of storage is in the branches
instead of the roots, will weaken the plant and result in smaller leaf size and shorter
internode growth. Pruning in the winter when the food storage is opposite of the
summer has almost opposite affects. Pruning the branches must be done in
partnership with the roots otherwise the plant will become unbalanced. (As
mentioned in “The Roots”.)
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Bonsai Development and Growth By Kelly Watrous
To control the change of direction in a branch is very simple. Wait until a bud is
pointed in the direction the branch should go and cut back to that bud. By cutting off
the terminal bud, the buds before it will break and start new growth. Then the new
bud will grow in the direction pointing adding to the visual appearance of the tree.
One key to keeping the shorter internodes and the smaller appearance of the tree is
to cut back the branch at the bud desired closer to the shorter internodes and only
leave two or three buds. Internodes naturally get longer and longer as the plant ages.
This will help keep the internodes shorter.
By continuing pinching or cutting back the branches at
buds, the tree will start to develop into a mass of fine
branches. A benefit to the mass is that there is only
enough room for small leaves to develop. It also adds to
the illusion of age as a well developed tree.
There are many things to consider when pruning a bonsai. Trim hanging foliage so
the branch structure isn’t hidden. Also, remove foliage in the crotches of trees
because mature trees never have foliage there; and keep space between branches
to avoid the bonsai from looking like a shrub. All of these pieces together combine to
create the illusion of an ancient, miniature tree.
My Interest
The main reason I chose Bonsai for a topic is my love of the Japanese culture. My
long term goal is to become a landscape architect. I want to use the Asian influence
(and other cultures as well) in my design and work. To understand Japanese
landscaping, one must understand the Japanese culture. There are a lot of people
on an island and they’re all wedged in between the ocean and mountains. That gives
little room for large, ornate gardens. Therefore, miniaturizing things is very popular.
In addition to the size, the meaning is influential as well. Zen, Feng Shui, and
Japanese Gardens are words that are given little actual
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thought, they’re essentially buzz words here. However, in Japan, they are the
cornerstones of their lives. Japanese garden designs are completely lost of meaning
when they’re created in other locations by people
who think they “look neat”. An understanding of
their religion and culture is necessary to
understand and create properly. I don’t claim to
have this knowledge yet, however I do respect
that we can’t imitate it without understanding it. I
also believe that with work, an open mind, and the willingness to understand I am on
the right track.
Ultimately, I want my designs, work, and even my personal self to be able to grasp
the culture and meaning. I don’t want to create something
that has no meaning, or where the meaning is lost on
myself and/or the clients. I want to be able to create
something that, even if it has no meaning to me personally,
it may have to my clients, and the final product represents
that accurately. And I want that to show. Very few people
have the respect for culture and nature that they should.
They want whatever is trendy and don’t want to research. I
want to show those people what is possible with the right
mindset.
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References
History
“Bonsai History.” The Bonsai in Asia Guidebook, Website.
http://www.geocities.com/Tokyo/Palace/7574/bonsaihistory.html
Hubik, Dan, “A Detailed History of Bonsai.” The Bonsai Site, Website.
http://www.bonsaisite.com/history1.html
Celestial Bonsai, “History of Bonsai.” Celestial Bonsai, Website.
http://www.celestialbonsai.com/history.html
The Roots
Meislik, Jerry, “Improving the Roots of Your Bonsai.” The Art of Bonsai, Website.
http://www.bonsaihunk.8m.com
Walston, Brent, “Root Pruning.” Evergreen Gardenworks, Website.
http://www.evergreengardenworks.com/articles.htm
Bonsai4Me, “Repotting and Root-Pruning Bonsai.” Bonsai4Me, Website.
http://www.bonsai4me.com/Basics/Basics_Repotting1.html
The Trunk
Walston, Brent, “Developing Large Trunks for Bonsai.” Evergreen Gardenworks,
Website. http://www.evergreengardenworks.com/articles.htm
Lewis, Colin S., “The Aging Process of Trees: Discover how trees age naturally and
learn how to imitate this on your bonsai.” Ho Yoku School of Bonsai, Website.
http://www.btinternet.com/~colinlewis.bonsai/Reading/Aging.html
The Bonsai Primer, “The Trunk.” The Bonsai Primer, Website.
http://www.bonsaiprimer.com/main.html#Index
The Branches
The Bonsai Primer, “Branches - Developing.” The Bonsai Primer, Website.
http://www.bonsaiprimer.com/main.html#Index
Walston, Brent, “Understanding Pruning.” Evergreen Gardenworks, Website.
http://www.evergreengardenworks.com/articles.htm
Walston, Brent, “Pruning and Pinching.” Evergreen Gardenworks, Website.
http://www.evergreengardenworks.com/articles.htm
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