Hort. Report






  When I, in brief, look back recently growth condition of Azalea, I think there are some minor problems about its plant maintenance.
  First of all, I would like to point out that concerning the method of pruning.     On the other hand, I want to say the problem of poor growth rate  that cause from physiological response or stress.
  I think that rapid  wound-healing in plants is as important in the fight against infection as it is in animals.  Generally speaking, an opening made in  phloem tissues is sealed by the exposed cells on the wound surface which collapse and die.    Scars on tree trunks, and branches with well-established secondary growth, are first covered with callus, parenchyma tissue arising from the division of cells near the wound surface. 
   However Azalea has poor recovery system for wound healing and different morphological feature on callus, parenchyma tissues that emphasize the growing strength of plant and prevent water loss.      Some plants, as you know, have inadequate morphological feature, so they often can't avoid severe damage like rot, insects, fungus and water loss.   Section of pruning and unacceptable judgment on pruning period are very important elements to avoid damages.
  Potentially shrubby trees have hardy characters indicated right picture.  This picture shows Azalea's powerful life-line like shoe string.  The trunk get damaged more than 80% of it's whole surface.  I could easily expect that it was survived until last storm. 
  To prevent the case I suggest gradual trimming and pruning  in accordance with each biological character through the year.   So we should keep in mind to carry on proceeding pruning for developing new growth as fast as possible.  We also should make sure however outlook of plants, growth condition and surrounded circumstance are.    Actually Azalea is one of very hardy plants, but we should avoid hard pruning, in particular old big trunk, as much as possible.  I wonder if we should set more concrete described guideline or something like that on pruning, especially hard pruning and how to keep naturalistic habitat, to make the garden more impressive.
  If we put on this standard pruning guideline, we can definitely get balanced shaped outlook of Azalea and keep more peaceful naturalistic scene in it as result.  According to these treatments, we can always come to see best condition of showy appearance in those areas.  I consider that trimming consisting upright open shape and mulch trunk structure will provide unique protection against external damages whenever we have stormy weather.   Needless to say, sustainable pruning also provide neat outline of plants.

Merit of mulch trunk style 
 1.   Easy to judge renewal pruning needed.
 2.   Reduce destructive damage caused by nature phenomenon.
 3.   Get lots of flower and last long blooming.
 4.   Enlarge  capacity of the photosynthetic process.
 5.   Keep sustainable attractive outline of plants.

These show three cases how develop new growth after hard pruning below.


*  Above left chart means pruning section with no branch to follow up.   New growth come up from basement close to roots.     A lot of parts died back because of dryness and physiological stress.   Start getting disease,fungas and rottening aggressively.
Struggling for existence.

*  Middle chart means pruning section with singular branch to support.  Part with no branch wilt and die.
Supportive branch occurs new growth.

* Above right means recommended pruning with minimum damage and new growth.  Speedy recovery at opening made from trimming.
Healthy reddish surface of bark.

    Whatever I would like to say about rough treatment on wound healing after pruning and expanding died back xylem tissue caused by them.  In spite of their severe damage caused by careless pruning, the fact that people, who have no doubt the report horticultural pastes have no good effect for woody plants, doesn't take care of wound healing after their pruning in The Western. I couldn't imagine that at all. Lots of Azalea have gotten not only physiological damage but physical one because of dryness, rotten and died back of wound parts.

I suppose that its hard to say one word whether recommended pruning methods are available for the plant, in particular Azalea, or not in those cases. But I believe that this method is very helpful for plants at least to develop parenchyma tissue around wound area. After all, we should pay attention with our considerations to each wound care problem according to physiological characters. So we sometimes need some kinds of wound care treatment like horticultural glue or paste in future.