Purplish spots on Vanda and Ascda

[JenHowlett]

The photos below are my young Vanda and Ascda hybrids. I noticed (along with the yellowing bottom leaf on the Vanda) these purplish spots along the leaf sides of both plants. I know a slight reddening on the edges and undersides of Phal leaves is normal, but it doens't look quite right on these. I'm not certain what could have caused this.

1) Its been warm here over the last two weeks (70-85F during the afternoon) and in preparation for moving outdoors for the summer, I put them outside in the sun (usually a little before noon) for 30 min (I set the timer on the stove) so that the move won't result in sunburn.

2) The plants live on the windowsill, leaves 2-3in from the window (there's a screen between the plants and the window proper) in a southern/eastern window to get maximum exposure, which until about two weeks ago wasn't much to speak of. I've been leaving the windows barely cracked the last few days to maximize air flow and its hasn't been too cold at night (55F at the lowest), but maybe they've been a little chilled?

Is there another culprit which I haven't thought of? You'll notice they're potted in coarse bark, not the typical Vanda baskets. They're young plants and haven't developed much of a root system yet (maybe a total of six inches of root per plant, though that's five more inches than they had when I got them), not to mention the humidity here is still pretty low so I don't have much root or humidity to support them in a basket. I soak 1-2 times per week (depending on conditions) and mist daily in an attempt to keep the humidity up. The roots are in good shape (fat, greenish-white, turning green as soon as any water hits them) and growing fast (that Vanda root you see growing over the leaf in the photo has grown over an inch in the last week), though I did notice that the bottom leaf on the Ascda looked slightly wrinkled, so perhaps its a little thirsty? I have a Vanda/Ascda hybrid of the same size(not pictured) that looks green and healthy without the purple spots and yellowing leaf and its kept in the same conditions as these two.

Any help or advice you can give is much appreciated- I know a Kentucky windowsill isn't necessarily the best place for Vandas, but the heat and humidity will be up in just another month and in three months we'll be moving to southern Texas and I think they'll really be happy there. Also any ideas for better culture (how to anchor in pot/basket- you'll notice my wiring job on the Vanda) are also welcome.

[tinabee]

I used to own Vandas, but gave up on them because they were just too high maintenance for me. I would think that even in pots they would still need watered fairly often. As soon as the roots look even the least little bit silvery, soak 'em down. Vandas don't like to be dry for very long. When you get ready to mount them in baskets, you will have to water them daily, in dry Texas heat, twice daily. When mine were basketed, the roots were very long and hanging. Here is a pictoral on how to mount a vanda in a basket:

http://www.orchidworks.com/potting/vandapix.htm

As far as the leaf spots, this is common with Vandas. If water droplets are on the leaves, and strong sunlight hits them, they will get those little burn spots. Not a big deal.

As far as the leaves turning purple, my phals. do that as well. That is actually a good thing....you are giving the plant enough sun. When the leaves have that purplish tinge to it, that could mean the flowers either have purple or pink coloring in their lineage.

That new root is also a sign the plant is healthy. Unhealthy plants don't generally grow new roots like that.

I say, keep up the good work!

[orkie]

I agree, those purpley spots on vandas are pretty normal, I get them on all of mine in strong light.