Smaller flowers?
 

I'm wondering what can cause an orchid (in this case phalaenopsis) to produce smaller flowers, each time a new one opens. I'm pretty sure that it's a cultural issue..

I tried to find some answers, but I wanted to see if anyone else has run into this problem.
So far, I've read that: temperatures are too high, not enough fertilizer, or too much light.

Could the size of the flower be reduced if the plant is also actively growing a new leaf and/or several new roots?
I read that a plant will save the nutrition it receives, and energy for new roots first, leaves, spike, and then buds/flowers last.

Sorry for another dumb question!

I'm going to say flat out, I don't know.

But I'm also going to say it's very common in plants in general that later flowers in a spike will be smaller than the first ones to open.

Now, I'm going to theorize from the plant logic point of view, the goal of the plant is to produce seed and the latter flowers are simply backup, in case the earlier ones didn't manage to get pollinated, or were eaten, etc. Given that logic, during the development stage, the majority of resources would go to the 'older' flower, it would seem to me.

Given your logic, if the plant is not threatened, yes, flowers should be a last priority, as is usually the case, when plants won't bloom :) Conversely, if the plant is about to die, many plants will throw a last ditch effort and produce flowers and hopefully seeds at the expense of the plant in general (not speaking orchids per-say, though I'm sure they do something similar).

Thanks for the reply! I picked out a phal (violacea hybrid) that has two phals potted into one pot. One is is bloom and the other is in spike. I think they're competing for nutrients as well.. Both are also growing new roots.
I might post a photo once the 2nd flower fully opens. :)

Another phal also has smaller flowers; that one is growing new roots and a leaf. The size difference isn't that noticeable.

So long as it has healthy roots and is in a good potting media, you are feeding lightly with fertilizer and it appears happy, I wouldn't worry about it. Some may tend to do that worse than others. If it is blooming (and not as a last survival attempt) it must be reasonably happy.

I've been experimenting for years and I still can't figure out how to prevent that phenomenon. I had a cattleya with 18 flowers on it this year. The first flowers were 5.5" across, the very last flowers were 4" across. That's a dramatic difference. I also have a few orchids that don't do that. For some reason all the flowers are the same size on a couple of my orchids, no matter how many flowers it has. I do know that on some orchids, removing some of the buds will cause the remaining flowers to be larger than normal. Probably because the plant puts all it's energy into the few remaining flowers. Asian growers use that technique to produce large flowers that are more likely to win awards. In any case it's probably not worth worrying about.

I agree Tucker85, it's just what it is...enjoy it as it is. Though, we always want to know things about it :)

Thanks for the replies! when I was at the greenhouse, I noticed that many newer flowers became smaller.. It must not always be a big deal, like you guys said. :)

The shape and color are different that the first bloom though. I know colors can vary, but shape? The first flower is a deep coolish violet; my phone has a tendancy to lighten and add warmth. I know these aren't the best pictures; the color is off, and the details aren't great, but here's the flowers.

http://i1167.photobucket.com/albums/...pspakj5bes.jpg

http://i1167.photobucket.com/albums/...psov5jd6n3.jpg

http://i1167.photobucket.com/albums/...ps3zltxzcj.jpg

Flower size, color and shape are all dependant upon numerous factors:

Light (bright light intensifies the color)
Temperature (cooler temps intensify red color).
Nutrients (to a lesser extent)
Whether it is first, in the middle or last on the spike.

You can't do anything about the last factor, but you can try to work on the other 3.

Thanks FairOrchids! I'll keep that in mind. :)
I'm still very happy with both flowers, and most of all, the plant. I love the wide, light green leaves. I love the first flowers shape, and the second flower has a nice darker, intense color. If the orchid looks healthy, without unpotting it to confirm, then I'm happy.

I'm going to be repotting my new phals when they're done blooming; the exception would be if I suspect rotting roots in the sphag.
I've gotten some orchids books and I read about weighing with a kitchen scale. Luckily I have one around so I won't have to second guess, when it comes to watering in sphag. The weight increases almost 2x as much. :O