Defoliation
From BonsaiWIKI
DEFOLIATION
Defoliation is a process applied to deciduous trees by removing the leaves, either completely or in part with the following goals:
- Reduction in leaf size
- Regulate strength in the branches
- Increase the ramification of the branches
- Improve fall color
This may be complete defoliation or partial defoliation of the canopy.
WHEN TO DEFOLIATE
- Defoliation should be carried out after the leaves of a deciduous bonsai have hardened off in late spring. At this time the leaves may be stripped or the leaves may be cut, leaving the leaf stems (petioles) in place.
- Weak, or unhealthy trees should not be defoliated. Conifers should not be defoliated and have their own foliage pruning techniques. (See candle pruning).
HOW TO DEFOLIATE
In practice, leaves are removed either by a leaf trimmer, tweezers or plucked by hand, usually beginning after the spring growth has hardened off. By removing selective leaves, the resulting regrowth will be more compact and the leaves smaller than previously grown.
REGULATING STRENGTH
This method can be used to redirect strength in the tree and ensure that branches in the interior and lower parts of the tree retain their vigor. For example, if leaves are removed from the crown and periphery, the interior leaves which remain will be exposed to additional light and air during the regrowth period, and so grow stronger.
RECOVERY AFTER DEFOLIATION
A defoliated tree usually requires approximately one month to completely regenerate leaves. It should be well fertilized in the period immediately prior to defoliation and water must be supplied sufficiently to ensure that the tree's recovery is successful. Defoliation may actually be carried out twice in a season, but only on trees that are in perfect health. A minimum two-month recovery period should be allowed.
Within a few weeks the petioles will drop away and new leaves will appear. The regrowth will be weaker, leading to a finer ramification.
SPECIES TO DEFOLIATE
Most all deciduous trees and broadleaf evergreens can be defoliated with success, with some exceptions. In my experience, beech does not respond well to defoliation. Flowering trees may be forced to flower again if completely defoliated.
| Types of Pruning |
| Pruning | Drastic pruning | Defoliation |Pinching | Trunk chop | Thinning | Trimming | Root pruning | Root trimming | Decandling |
| Tools for Pruning |
| Concave cutters | Shears | Thinning shears | Decandling shears | Leaf trimmers | Scythe | Root cutters | Branch cutters | Spherical cutters | Knob cutters |
