Phal flowering issues

[karlos879]

I'm still very new to all this but I have been lucky enough to get hold of some cheap flasks and grow a number of phals this past year or so to add to my mature plants.

The problem I am having is this:

I am getting a good number of flower spikes on the mature plants, with good high stems, but most of the time (in the last 2 months or so) the buds appear, grow a little, then shrivel up and fall off. The plant then tries again to flower and the same thing happens.
They are split between a greenhouse and the house, and the same thing has happened in both locations.
What am I doing wrong here? Not enough humidity? Too hot?

Any help would be greatly appreciated.
Thanks,
Karl.

[rangiku]

Karlos, bud blast can be caused by several factors: temperature, humidity, air circulation and insects.

The temperature during the day ideally should be between 23C and 29C with nightly temps of 15.5C. Max daily high temp is 35C, but if it gets that high you need to increase the humidity and increase air circulation. Fluctuating temps can be a cause of bud blast. This is paraphrased from the AOS site.

Also, I've been told that some kind of mite-like insects can cause bud blast as they live inside the anthers of orchids. If you have a 20X magnifier see if you can see tiny red dots around that section of the flower or cut a blasted bud apart and see if you see anything in there.

When some of buds on my phals blasted I checked, but found no sign of mites. In my case, perhaps the buds died as I didn't have the fan on for a few days. I could kick myself for that. Live and learn and make different mistakes next time.

Good luck. Let us know how you fare.

[karlos879]

Thanks, I'm now pretty sure it will be related to the humidity in the house.
The greenhouse is good, but I think the problem is when I take them inside.
Thanks for the assistance.
Karl.

[Queenslander]

Where abouts in Oz. do you live?

[karlos879]

I live in Adelaide.
Karl.