Satsuki Going Downhill

[Troutsqueezer]

I've had a very nice Satsuki Azalea for around 6 years and it has been problem free until this last Spring when after the blooms dropped and one of the two primary trunks lost all of its leaves over the span of a couple of weeks. I hoped they would return but now it looks like they won't. Scraping the bark indicates that the branches may still be alive except for the tips of the branches.

The other trunk seems just fine but now I only have half a tree.

There were no signs of insects that I could see.

What are the possibilities?

The weather has been fine here in California and all my other Bonsai's are just peachy.

 

[Bonsai Nut]

Was there any other damage / leaf loss on the 2nd (healthy) trunk?

If the damage is very clearly restricted to one section of the tree, I would usually look to root problems - a section of roots died and the corresponding trunk/foliage mass followed. Did you recently repot or did the tree experience water shock?

 

[Leo in N E Illinois]

I have had Satsuki crash on me. One cause was drying out too hard between watering. (took a long weekend, two days too long, thought it was going to rain, it did not). The azalea completely defoliated, many fine branches died back. I thought it was dead but left the pot on the bench and kept watering it with the others.

About 6 weeks, more than a month later, there were little buds sprouting, mostly near the trunk. It is alive. Delicate health, but alive. lost all the old branch work, but I look at it as a new design opportunity.

So if irregular watering was the cause, don't give up too quick. If the cause was spider mites or one of the other mites, they are difficult to see and often are only identified by their damage. The tree will need to be sprayed if there is any chance to save it. There are a number of catastrophic fungal and bacterial rots that can happen. These are sometimes cured by moving the satsuki to a spot with better air movement. And sometime a repot will help to a more open mix.

Note, normally if the trouble was not caused by a root rot, repotting a weak tree can be a death sentence. Don't repot a weak tree unless you have clear indication it needs to be done.