I posted last week about my 3 year old Brazilian Rain Tree. Its leaves were turning yellow and falling off. The census was that it was stressed and I decided to water it a little more than usual. Its still in my patio receiving partial sun, but those darn leaves are falling off at an alarming rate. No pests that I can see.
The tree is stressed... this is why the leaves are falling off. Pest will not do this.
So, then we need to understand why this is happening...
A tree will usually drop it's leaves as a way of preserving itself from dying.
It does this because there is an imbalance in the tree's natural cycle of photosynthesis.
Leaves take in light and draw up moisture/nutrients from the roots. When there is an
insufficient amount of water, that is needed to complete the cycle, the tree will recognized
this and as a survival mechanisms, it will try and save itself, by shedding leaves.
Since cold is not a factor right now, there are only a couple of reasons why then
this might happen. The first, being that the tree is overwatered, and the roots are
rotting and not allowing the intake of water. Their has been damage done somewhere
in the tree, that is preventing or hindering the flow of nutrients. Whether through a
possible disease, or trauma, such as a severe cut, bend, or cutting of roots. Or Lastly,
through a lack of proper watering and to much sun.
So, for us to help you... and since we are in the middle of the hottest part of the year,
in Florida... bright and sunny, remember... Did you allow this tree to go un-watered for
any amount of time ??? How often were you watering it before this started happening ???
Once a day, twice a day, every other day, every other other day ??? Now be honest...
Since we know that it was in the full sun, and you have now moved it to the partial shade,
does it still get any direct sun ??? You say you have increased the watering... to how much ???
Lastly, what kind of soil is it in... a regular nursery soil, ie. dirt, and possible pine bark...
Or is it in a Bonsai Soil, with lava rock, pine bark, pumice etc...