Purple Leaves 101

[BunnytheOrchid]

I went to a local garden center (not the nursery I typically go to), and I saw a lot of very lovely orchids, but some phals had purple on the underside of their leaves, or almost entirely purple leaves starting from the crown of the plant. I have heard some purple leaves are normal; I've also heard that darker purple looking leaves are a sign of too little sunshine. So, my question is (as a new grower), how do you tell the difference between healthy purple and bad purple leaves??? Is there an obvious difference? Thank you o' knowledgeable ones!

[mayres]

I certainly DO NOT qualify as "o' knowledgeable ones", but I'll take a stab at making a few comments on this based upon my own personal experience. Purple on the leaves is caused by LOT OF SUN - not too little sunshine - just the opposite.
At the extreme limit I have dends that have turned totally red from too much sun - I can tell they don't like it - leaves start to turn a little wrinkled and the plant grows poorly. As new growth comes in I am backing off significantly. Have had similar experience with cattleya plants as well. A little red cast does not hurt a thing - but if they get redder and redder you better back off or you will soon have a dead plant. Phals I have also have turned reddish - but not to the same extent as my cattleya and dends - a little red tinge which I think is good - shows they are right on the edge. I've also noted that plants with dark pink or pink blooms tend to show red in the leaves more so than other colors such as white or yellow. So - my "just learning like you are" opinion is that a little red cast is good - total red is BAD. Good luck! mike

[kmarch]

To add to mike's post, some orchid species do have leaves with purple undersides. This trait sometiems gets passed on to some of the hybrids. This trait is usually perfectly normal and not a sign of too much or too little light.

[BunnytheOrchid]

Hmmm I wonder if I've been too cynical about orchids with reddish leaves :/ I didn't realize some red was still ok. Plus I thought too much sun/light caused the leaves to yellow and/or brown? I guess I should ask how do you know if they have too little sun?

And everyone here definitely qualifies as "knowledgeable"! I'm learning a lot from this forum! Hooray!

[kmarch]

Well I'm not exactly sure what "red" you're considering, but at least the leaves which are green on the top and purple underneath, at least that could be a result of breeding.

Generally (and I'm probably over generalizing too much here) light, leaves, towards the yellow-ish end is too much light. Dark leaves or tend to be the result of low light.

There's lots of exceptions to this.

[mayres]

To add just a bit more to what Kevin is saying - at least in my case - a little too much light gradually reddens my phals, dends, and catts - a lot too much light will turn the leaves yellow and brown and burn them off. Other genera like cymbidiums, zygopetalums, oncidiums for example - with too much light I have noted that they just become paler and paler and eventually yellow. Also a generalization, but this is what I've noted from my collection.

[BunnytheOrchid]

Hmmm I think my lesson for today is that if I buy an orchid with some purplish leaves, I'm posting a picture of it here to get some advice! Thanks everyone!

[PhalPal]

Moved from similiar thread: Purple leaves can also be a sign of OVER lighting. Usually the entire leaf will be purple, not just the edges as yours are. On some Phals purple edges are a natural coloring and nothing to worry about. I agree that it is ready for a re-pot, but if only the bottom leaf is wilting it just may be dying and lived out it's natural life. If it turns yellow and eventually pulls off easily and no other leaves follow suit, this is the case.

[BunnytheOrchid]

Hehe thanks phalpal. I'm not super educated on purple leaves, as you can see

[kmarch]

Originally Posted by BunnytheOrchid

I'm not super educated on purple leaves, as you can see

You will be before long! Let us know how it goes.