in s/h for 4 years but no flowers
 

I have a phal that has been in s/h for over 4 years, it is now in a 6" pot, it has never flowered for me. I believe it is getting enough light as the edges of the leaves have a red tint. The pot is almost full with roots. I use a balanced fert once a month. What am I doing wrong?

the only two things I can think of - light and temperature fluctuation.

I think a few days / weeks in the high 50s do a phal good when letting it know its time to flower. I could be wrong. I've read 3 or so weeks is enough...

Yeah, temperature differential could be it. I have 6 phals in semi/hydro. This year no spikes. I think because I have electric baseboard heat and no temp drop at night could be the cause. I am turning down my heater at night to see if it helps. I drop it from 70 to 60. I will post with joy if I get spikes.

Thank you for the reply's. The temperature was not considered as my thermostat is always set at 69.

I'm pretty sure it's the temp. issue. I give mine 3-4 weeks with night temps upper 50s and they all spike. I open the window in the room at night to get the cool temp.

What kind of / how much light does it get?

It is a natural light. It sit's on a south facing window sill. It sometimes gets supplemental lighting in the evening if I am using the room.

Mine are all in S/H. South window of a sun room. I have a seedling heat mat under them. A window fan in the east window, blowing "out" year 'round.

When I bring them in before first frost, I always leave a west window open a bit at night and close the door. Causes about a 10-15 degree temperature drop overnight, then I shut window in the morning. And shiver awhile, as it's also my office. :shock:

I do this for at least three weeks, sometimes four. Then never open that west window again...because I can't take it anymore. ;)

If you can get the temp drop overnight, I'll betcha you'll have spikes thereafter. Once I started that regime, I got blooms that hadn't been seen in several years. :biggrin:

http://www.orchidboard.com/community...-blooming.html

Others mentioned temp, but here's a more scientific study about temp in Phals if you're interested.

A thermostat with multiple time/temperature settings would do the trick.