I have KeikiGrow Plus lanolin-based paste from Plant Hormones Canada. The paste is viable, and I have recently used it to stimulate another spike on a Phal.

Unfortunately, I have not been too successful at using this product to actually produce a keiki.

I have a Phal that I would like to propagate - P. ELEGANT DEBORAH (Syn. Taida Pearl) that is currently in bloom. Last bud opened maybe 2 or 3 weeks ago.

My understanding (from reading on the internet) is that stimulation of the nodes closest to the flowers have a better chance of producing a spike, while nodes further down on the stem have a better chance of producing a keiki (if this is incorrect, please let me know). Also, I've heard that allowing too many nodes to develop keikis can stress the plant; best to limit it to 2 or 3 keikis and provide ample water and adequate fertilizer while the keikis are growing.

Here is my main question: How old should the spike be before I attempt to induce keiki formation? Should I do now while in full bloom? Wait until some flowers drop? Wait until all flowers drop?

Opinions appreciated - especially from folks that have succeeded in using hormone products to produce keikis.