Healthy green Phal leaves falling off!

[JKah]

Hi all,

I'm relatively new to orchid growing, and have 2 orchids, both Phals. One I've had for 2 years and is healthy, the other I've had for 9 months and has dropped 2 leaves in 2 days.

It was potted in moss before, but this wasn't draining well and led to some mushy roots so after it stopped flowering I cut off the flower spike and repotted it in bark, removing all the dead roots too (which was most of the roots). When I repotted it, the air roots which I tried to fit into the pot snapped near the base but are still attached and seem to still be green where they are submerged. I only water it once per week, or less, once the roots are dry.

Now, a month or so after repotting, two of its largest leaves have fallen off whilst they still look healthy, with a really clean break. See attached pictures.

Can anyone provide any advice on what might be wrong and what I can do?

Thanks!

JK

[oile]

Suffering of the roots.
In my humble opinion the main cause of the suffering of the roots and the second external vase; the phalaenopsis needs air and light in the roots.
To regulate how to irrigate these orchids is to immerse them in water until the roots turn green and do not wet again until they come back gray again.
It needs good ventilation and exposure to lots of light, but not direct exposure to the sun.

[JKah]

Thanks Oile!

That makes sense about needing light and air. I will make that change.

Are there other changes you would suggest I can make - e.g. repot in moss, move to a humid, warmer, sunnier room, etc...? Or do you think this orchid is probably over now - it has now lost its 3rd and last big leaf, the only other leaves left are small (2-3 cm) fresh leaves.

Thanks!

[raybark]

It needs more water, too. There is no need to wait for the thing to dry out between waterings.

[Dorsetman]

The usual reason for leaves falling off, when good and green, is cold.

[oile]

Thanks Oile!

That makes sense about needing light and air. I will make that change.

Are there other changes you would suggest I can make - e.g. repot in moss, move to a humid, warmer, sunnier room, etc...? Or do you think this orchid is probably over now - it has now lost its 3rd and last big leaf, the only other leaves left are small (2-3 cm) fresh leaves.

Thanks!

The temperature should not fall below 15 °, do not exceed the sphagnum or moss or it will retain too much moisture, it requires a lot of diffused light.
A treatment with Previcur Energy (Bayer) could help.