Flowering & Fruiting Bonsai

By Artis Dave Paris

Flowering & Fruiting Bonsai

One of the true joys of spring & fall for deciduous bonsai are flowering and/or fruiting species.  These tend to be fairly hardy and easy to care for.

The primary difference between fruiting/flowering species and other deciduous types is in the timing and planning of pruning.  Some species only flower on old wood while others flower only on new wood.  If you’re working with a species that flowers on old wood, the time to prune is just after flowering is completed for that year.  If you’ve got one that flowers on new wood, prune during repotting in the late winter or early spring.  If you’re unsure, consult reference manuals like Dirr’s Guide to Landscape Plants, other reference manuals at a library, or on the internet.  If you have a species you’re sure is a flowering one but has never produced flowers for you and you prune in spring, odds are good that you have one that flowers on old wood.  Styrax japonica (Japanese Snowbell) is a more common tree to fall into this category, as are flowering quince and crabapple.

If you’re in a branch development phase, it often helps to remove the flowers early in their appearance for the year due to the energy required for flowering and fruiting.  This allows more of the plant’s stored energy to go into activating latent buds that help create branch ramification.  During the fall, selective reduction of fruit also helps the plant by reducing energy expenditure, allowing it to store more energy for overwintering and new spring growth.

During development of secondary, tertiary, or further ramification, it’s often best to forego flowering and fruiting altogether.  In late winter or early spring, before buds start swelling, prune for shape, leaving one extra bud long on each branch.  This is also a good time to remove congested branchwork, making way for a replacement.  By removing terminal buds, the auxin signal to the roots is reduced and the plant responds by activating latent buds, usually with the strongest response being towards the end of the branch.  If repotting is done at the same time, the total amount of stored energy from winter is reduced and the amount of cytokines coming from the roots to the branches is also reduced.  This has the effect of shortening internodes considerably.  This work is best done while the plant is still dormant, but temperatures are rising which reduced the likelihood of dieback.  This energy management and re-distribution is not unlike the methods applied to pines, only the timing changes.  Usually a second pruning is carried out in late spring or early summer.  By the end of summer, pruning is put on hold to allow the plant time to store maximum energy for the coming dormancy and following spring growth.  The tree might look a little shaggy, but it’ll be in prime shape for the following spring.

When styling flowering and fruiting species, apply wire when pruning and carefully twist or bend branches to place the flower buds on the outside of the silhouette.  This will give the best visual impression during flowering and fruiting with the minimal amount of flowers, allowing the plant to retain as much energy and vigor as possible for good health and growth.  Because flowering species tend to be somewhat brittle, it’s often a good idea to combine wiring with clip-and-grow pruning to give the most movement with the least stress and potential for breakage.  By retaining one extra bud beyond the one you want to keep, you give yourself a little insurance from possible dieback and accidental breakage.  Once the leaf buds expand at the point you want, you can then remove this extra bud at the end of the branch.  To effectively style flowering and fruiting species, an understanding of the nature of that species is crucial.  Some do not produce dense branching while others have long internodes.  Understanding these nuances and using them helps to select appropriate lengths and directions to create the appearance of a well-ramified and lush tree.  Even on species with longer internodes or coarse ramification, careful attention to pruning and energy management as detailed earlier can help by encouraging back-budding to fill in gaps.  The understanding of the species also helps direct the most effective style for any given material.  One with coarse branching may lend itself to a literati style while another with very dense branching but slower growth might work better as a clump style.  Don’t hesitate to try various nursery materials from garden centers.  What we in the West consider unsuitable is commonly used in the

for their wonderful spring, summer, or fall flowers.  Select materials with flower or fruit sizes appropriate for the final bonsai size you envision.  There are numerous dwarf or pygmy cultivars for many species that lend themselves quite well to bonsai – even something we consider to have massive flowers, like Hydrangea!  While bonsai techniques can considerably reduce the size of leaves, flowers and fruit do not respond in this way.  What you see is what you’ll always get.

By keeping detailed notes and doing research, you’ll end up with a plan that doesn’t stress the tree terribly and produces a wonderful bonsai that will delight you for many years!

Pruning Detail:   (late-winter/early spring before, after, and second pruning)