by Jerry Meislik
There are hundreds of Ficus species in the world. Many make great bonsai while others for one reason or another do not seem to work as well. One possible reason that a plant may not succeed as a bonsai is the leaf size. In order for the visual perception of a bonsai as being a "real, full-sized tree" is the scale of the leaves relative to the whole tree.
Naturally the smaller the leaf the more in scale it is to the whole bonsai. To a limited extent one can moderate this relationship by growing a larger bonsai from material that has larger leaves; in that way the whole design remains in scale. Another technique is the reduction of the leaf size that is possible with some species. Leaf reduction can occur due to constant trimming of the tree, maintaining the tree in a small container, limitation of nutrients and water, and defoliation. For information on.
One plant that I have been growing since 2004 was given to me by my good friend David Fukumoto of Fuku-Bonsai. I call this plant Ficus microcarpa 'Mini'. It is a possible hybrid of Ficus microcarpa and Ficus microcarpa 'Taiwania Ovata'. The plant that he gave me has been kept in a small container for nearly all its years. The leaves are quite small at about one inch in size. I have kept it trimmed back closely to maintain its shape and diminutive size, height about 4". I wondered how big its leaves would get if not restrained. My experiment involved two ideas. One was to grow cuttings from the mother tree and two, graft a piece of it on normal microcarpa stock.
The results of the experiment show that the un-restrained leaf is quite a good deal larger than that on the mother tree - at 2 plus inches - at least twice as large as on the mother tree. Even so the leaves are smaller than with most of the Ficus microcarpa making this cultivar very useful for small sized bonsai.
My conclusion is that this cultivar of microcarpa has very small leaves under typical bonsai cultivation. When grown without bonsai restrictions it has much larger leaves. This is typical for most Ficus bonsai under bonsai culture.
When evaluating a plant for possible use as a bonsai it is worthwhile to consider that the leaf size may be reduced in cultivation. Plants grown in the ground or larger pots and not trimmed will have leaves several times larger. Leaves will also be larger on plants grown in low light.