Why won't my vanda root?

[Synrosion]

This fertilizer I have for my orchids does wonders for my other vanda. It mixes superthrive vitamin solution, A 20-20-20 fertilizer, and a kelpak. All my orchids love it but my two hanging large vandas don't like it as much? What should I be doing better?

[Ray]

Superthrive contains a synthetic hormone, so unless the active chemicals have degraded with heat, light, or time, it should not be used with Kelpak - pick one or the other.

Also, generally speaking, Kelpak should not be used more frequently than every two weeks.

How much fertilizer are you using, and how often are you applying it?

How are you growing the vanda? Potted, basketed, what medium, etc?

[estación seca]

And, how are you watering? How much? How often?