I have had this plant for over 4 years now. Every winter it produces a tall flower spike with white flowers which last a very long time. It appears to be growing well however compared to my friends orchids it never has more then 3 leaves on it...is this normal? I think once it grew a 4th leaf but then immediately the oldest leaf turned a beautiful yellow/red and dropped off...am i doing something wrong?

Considering your plant gives you flower spike every winter is good growing already!

Yeah, it is quite normal for older lower leaves to die off first. As long as it manages to make a new leaf, and the roots remain healthy, then your plant is doing good!

I don't know if you notice it, after bloom time is over, the plant rests, then goes active again after a few weeks doing new roots then one or two new leaves. And as you said you get blooms during the cool period. They do make their bloomstalks towards late Fall when temps goes cooler, so the timing of your plants blooming is just right too. My Phals sometimes lags a bit behind, will do the blooms more towards Spring, but typically it would have started bloomstalks by late Fall, maturing all throughout winter till it blooms in Spring.

I love Phals, their blooms last very long when care is met properly. We all have varying growing environements, so it is hard to compare ones plants to others. But as long as your plant is giving you good growth, that is just quite okay!

@Pier Considering All the aerial roots... could this Phal be telling you it Needs to be repotted in fresh bark/mix? How long has it been in this pot?

3 leaves is not normal. 5-6 leaves is normal. Really healthy ones carry 8 leaves.
Yours is not holding enough leaves. Yes it is blooming every year, but how many flowers? I can't tell you how many would be appropriate without knowing what it's linesge is.
You need to fine tune your culture!!!
Repot every two years at least.
Fertilize 1/2 strength no more then 4x per year.
Make sure the leaf color is good and the light is proper.
Watch your watering, never let it get too dry.
Make sure it is between 60-80 degrees.

I say to fine tune your culture because when a Phalaenopsis is stressed when not in bloom, the first thing that it might do is drop a leaf. Or stressed in bud or bloom, there are fewer flowers, slightly smaller flowers, or buds drop off.
Also very important, after four years it should have 5-6 leaves easy. You obviously can grow it but a little extra care is needed!!
Good luck!!

My Phal has 12 leaves plus one keiki (which has 4 leaves), but never produce any flower spike.

The vast majority of Phalaenopsis will bloom without any kind of incentive. You just grow them and they bloom every year.
There are 2 reasons that they do not bloom.
#1 too much fertilizer. A small percentage of Phalaenopsis do not bloom if they get fertilizer too often. Some people say you should fertilize them with every watering. Also known as the weakly weekly fertilizer program. With fertilizer being applied to often and too strongly, this is what could happen, a lot of leaves but no flowers. From what little information you provided, this is what I suspect is your problem.
How often do you fertilize. How much do you fertilize? What kind of fertilizer do you use? 20-20-20?
#2 Lastly and also not that common, there are some Phalaenopsis that need a night time temperature drop of AT LEAST 15 degrees or they won't flower. This doesn't happen that often but it does happen!
This temperature drop is required due to species/hybrid background. If you grow it in a narrow temperature range of between 68 and 75 degrees all year round, they may not flower. Make sure that yours is getting a decent night time temperature drop.
Naturally this is far more common with indoor Phalaenopsis growers!! It usually can be a drop for a three week period in the fall sometime. Say mid September through late October.

Sometimes I think genetics sets in too, a lot of Phals are hybrids, so depending on what combination it has in it, it may affect its growing habit. Of course observing its cultural needs is important, but I do not fret with the number of leaves, My Phals can bloom with much less at times just 4 leaves, but my goal is for the growing cycle to continue on, after blooming to allow it to rest, make new leaves and roots that it can and later the blooms.

BigBill said:The vast majority of Phalaenopsis will bloom without any kind of incentive. You just grow them and they bloom every year.
There are 2 reasons that they do not bloom.
#1 too much fertilizer. A small percentage of Phalaenopsis do not bloom if they get fertilizer too often. Some people say you should fertilize them with every watering. Also known as the weakly weekly fertilizer program. With fertilizer being applied to often and too strongly, this is what could happen, a lot of leaves but no flowers. From what little information you provided, this is what I suspect is your problem.
How often do you fertilize. How much do you fertilize? What kind of fertilizer do you use? 20-20-20?
#2 Lastly and also not that common, there are some Phalaenopsis that need a night time temperature drop of AT LEAST 15 degrees or they won't flower. This doesn't happen that often but it does happen!
This temperature drop is required due to species/hybrid background. If you grow it in a narrow temperature range of between 68 and 75 degrees all year round, they may not flower. Make sure that yours is getting a decent night time temperature drop.
Naturally this is far more common with indoor Phalaenopsis growers!! It usually can be a drop for a three week period in the fall sometime. Say mid September through late October.

It could be both...

I grow it indoor (temperature in the house is between 64-70 degrees all year round)

I fertilize with an 'Orchid liquid plant food 15-5-5' one drop with about 250 ml of water every 2 week (it said on the package using 7 drops per liter of water every time you water)

See newen, 15-5-5 is perhaps too much nitrogen. I use 20-20-20 at the rate of 1/2 tsp. Per gallon but once a month.
I know that those 20-20-20!numbers look like a lot but it is much less frequently applied.
Now here is a trick for you to try Pier and newen, when you see that the days are getting shorter, we are heading into fall, move your Phalaenopsis into a room for two weeks, turn down the heat in that room, close the door and open a window a little. Use a little oscillating fan to move the air. It will drop the night time temperature enough to promote spike production.
You can do the same in the spring. They need a good two weeks of lower night temperatures to initiate spikes.
64-70 should go to 55-70 and after the two weeks, see if you get bloom spikes. It may take 4-6 weeks before you see them but you will see them.
And if they were mine, I would fertilize once a month at most.

I agree with you it's too much nitrogen.

What a great ideas! I will definitely try that!

Yeah newen!
I'm 🕺

Thank you so much for your help everyone! So ok I won't worry too much as the flower spike is tall and gives quite a few flowers, thought I had a picture but I can not find it.....I do tend to cut the stem down at the base once all the flowers have ropped off however I get told I should leave it to see if it grows new flowers or indeed a keiki is that right? On a website it also says if you cut it below the first knot it encourages more flowering but I am not sure if they mean the first from the base or from the top....

With regards to the roots groing out are we all in agreement it should be repotted based on this? I thoughts many air roots were a sign of a healthy plant.

BigBill I have started to use Biopon Orchid fertiliser now with all my orchids. It is now very warm in the UK with temps reaching 30 degrees celcius (86 F) so watering twice weekly and keeping the windows open.

My other concern is with the Oncidiums i have. When I posted pictures of both I was told they looked very dry and need watering however since I have been watering more one of the bulbs rather than growing fatter turned its leaf yellow and it dropped off and looks like it is dying. Given they are in a plastic pot I cas see the roots and I have a feeling that the orchid may not be getting enough water due to root rot as some roots look yellow and damp. The medium is coarse but does not usually dry fast due to the high humidity level in my flat......so although I am wateirng more I do not ever get the feeling that the media is ever completely dry. What should I do?

Oncidiums like even moisture, never going completely dry. If your watering schedule improves, the overall health will improve.
As far as reblooming a Phalaenopsis, that is a matter of the overall age and condition of the plant.
1- a seedling or young Phalaenopsis should not be allowed to rebloom on a spike. In most temperate climates, after the flowers fade, the plant should be allowed to make new leaves which are good for the overall health of the plant going forward. They should NOT be allowed to rebloom just to make their owners happy!
In sub-tropical climates, where leaf growth is constant, they can be allowed to rebloom.
2- a mature Phalaenopsis, one with 5 leaves or more, a minimum of a 12" leafspread, those plants have enough reserve strength to have the energy to produce more flowers.
It is advisable not to have it reblooming from the tip of the spike but more towards its base!!