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astridc_gw

brown spots on phal leaves - Help needed!!

astridc
16 years ago

Hi everyone,

I am a newbie with orchids. I bought my first one around 4 weeks ago- a phalaenopsis with purple flowers (and I love it so much!!!) I bought it already in bloom, with 2 flower stems.

I have noticed recently that some brown small spots have appeared on the bottom of one of the leaves, on the outer rim of the leaf. This particular leaf sits upright with the spotted bottom side facing the window.

What could have caused this? what am I doing wrong?

I am growing it on a closed balcony, north facing but well lit as I live in a high building, on the 10th floor.

Temperature was high until the end of August 71 F at night, 85-90F at day. Now in September it's getting colder, 53F at night and 62-65F at day. Eventually I am thinking of moving it indoors as it's getting colder.

I have been watering it every other day by dipping the pot in a bowl of tap water and then letting the excess water drain from the pot. Adittionally I spray the plant with water.

For one week when I was away, it did not receive any water as my sister forgot to water it and one of the leaves turned yellow and dried out, some of the unopened buds also dried :-(

What could have caused the spots? am I doing smth. wrong? too little light? too much/little water? Any help from you experts much appreciated!!!

thanks a lot!

Astrid

Comments (12)

  • richardol
    16 years ago

    Cut back on the watering and bring it in. 53 is already too cold for Phals to do well and watering once a week is healthier for them than what you are describing. In fact, it is possible that the roots have rotted already.

    Get a #2 pencil and, after a week of no water, push it down the inside edge of the pot. Give it a twist and see how wet the wood is. Do this daily for awhile until the pencil is only a little moist. Then water really well.

    Lots of water, getting every part of the pot wet. I personally don't use the dipping method, rather taking it to the sink and using the sprayer to wet everything. Keep water out of the center of the plant. Read the FAQ at the top of the page.

    Good luck with bringing this plant back.

  • michigoose
    16 years ago

    Also, what are the spots like? Are they sunken? Are the raised bumps? The raised bumps could be scale which is an insect. Sunken spots could be cellular collapse from cold and or other critters.

  • claritamaria
    16 years ago

    Could also be rot from misting. I don't like to mist. It invites trouble

    Clara

  • bevo_2007
    16 years ago

    I also have small brown spots on the underside of my leaves, near the crown. The spots wipe mostly off, but leave a black spot. The brown spots seem to be powdery, like a fungus. I am not an expert, but it looks to me like small areas of the underside of the leaf are rotting, and the fungus is growing from the spots. Could we get an expert's thoughts on this? Also, how does one treat the problem. I wiped the underside of the leaves with rubbing alcohol.

  • howard_a
    16 years ago

    Decades of North American and European greenhouse growing (sorry Richard!) have led to the watering wisdom that we live and die by. Why, because in a greenhouse the amount of light you have is a fixed function of your geography. In NA/EU the light available in many regions is simply insufficient to sustain tropical orchids even in a greenhouse. Luckily workarounds have been discovered. Systematic underwatering is one of them. It is the exact opposite of what the orchids want. Orchids want never to dry out! Their whole existence is an attempt to preserve moisture this is why they favor parts of the world where there is a large moisture reserve in the air itself but also in the many crooks and crannies of the bark mounts. Why then do we practice routine dessication of these plants? Instead of checking for moisture to avoid overwatering we should be checking for dryness to avoid underwatering. Well that is what we should be doing but mostly it doesn't work and the reason is/must be that the plant is underlit. If properly lit a normal, even insane amount of overwatering is not harmful. Overwatering is not the reason orchids sicken. Lack of light, lack of adequate temps, anything but too much water.

    In the case of Astrid's and Bevo's plants in addition to a chronic lack of light I also suspect a lack of air circulation and possibly too low temps. The misting hasn't helped as Clara observed. In short the reason is cultural. Environmental to be specific. When orchids sicken look to their environment the answer will be there somewhere. Don't look at the plant or in the pot. Those are the end stage symptoms. You can of course fix things up with fungicide or alcohol or other palliative but the symptoms will return without a wholesale overhaul of the entire environment. Start with light and work down through the other parameters until you have what the plant needs. Anything less and the "help me" posts continue.

    "I am growing it on a closed balcony, north facing but well lit as I live in a high building, on the 10th floor." You don't have to take my word for it, the orchids are telling you that there isn't enough light. Unless there is some SUN, all the bright, indirect light in the world will not be sufficient. Even low light plants in deep shade get SUN. Every second or three the leaves of the covering trees have uncovered some portion of the orchids surface so that it is exposed to full sun. It may only be for a second but in the very next second another patch of orchid is in full sun and so on and on, all day long. No flowering plant grows where there is no sun at all, only reflected bright light.

    H

  • highjack
    16 years ago

    bevo brought up a very old thread. bevo you probably have a small fungal infection growing where the leaves meet the crown. This probably occured with water left in that area after watering the plant.

    Cleaning the area with alcohol was fine - do it this time with regular, over the counter peroxide and immediately apply cinnamon to the discolored area. Be sure you dry this area and leave no standing water in it. Hopefully, the plant will recover but if it doesn't, you will know to watch the area the next time.

    Brooke

  • t_bred
    16 years ago

    Astridc, How big/small are the spots? I am curious if they might be mites? I am battling myself right now, and they seem to have a preference for the underside of leaves(especially phals) and they seem to convene on a central location making a bunch of small spots seem large. Any other opinions about mites?

  • jane__ny
    16 years ago

    I use alcohol on mites. I get some on Phals and hard-cane dens. Every year, about this time I see the scars, I never see the insects. I won't use anything heavy-duty indoors, some alcohol on a cotton ball or tissue will carry them until they can be treated outdoors.

    Jane

  • t_bred
    16 years ago

    Thanks Jane, trying the alcohol thing myself. Just wondering if mites could be what Astrid has going also.

  • astridc
    Original Author
    16 years ago

    Hi everybody and thanks

    I found another post that describes my problem perfectly. http://forums2.gardenweb.com/forums/load/orchids/msg0919564423909.html?11

    So according to this post it seems the problem was too much light ?!
    Actually now the spots disappeared but the leaf is still curled -
    I moved the plant inside at the end of September and it seems it likes it. I think it also likes misting - I have misted it for several weeks and two of the buds opened.

    I did not mist it for a week then and the last bud sadly fell off...

    So I think I will stick to misting it every other day and water it every week with a little fertilizer, as I do now.

    I cut the spikes above the third node from the base now. I will see how it likes it.

    Astrid

  • claritamaria
    16 years ago

    May I ask the OP where they have gotten their basic information culture information? I am curious where this information comes from. I see it many times from people new to orchids.

    I see nothing in the other post that states " Too much light". In fact I see the opposite many times over from experienced growers. I don't understand how the OP arrived at too much light conclusion. A Phalaenopsis is a tropical plant in a non-tropical environment. A Northern exposure and 50º temps would not benefit a Phalaenopsis or any other tropical flowering plant.

    Would you describe your present indoor conditons & culture?
    Would you tell us what steps you have taken to cure the "brown spot" problem?
    Would you be able to provide a photo?
    Would you tell us where/ when the plant was purchased?

    The OP has a declining plant. Spraying and misting cures nothing and can cause a variety of problems. You have a yet to be determined problem (I'd wager a lack of light). You have let it go for a few months. I would suspect your phal's problem has not improved. I strongly suspect you will face even greater problems quite soon.

    Spots don't disappear unless these were spots caused by a sudden shift in light (more) which happens in the fall months. You have brought it inside and the plant is now underlight, "darkening down". The spots would disappear under those circumstances. Plants leaves get darker the less light given. This is not a good thing.

    There is nothing that resembles Phalaenopsis culture (care). Buds don't stay forever. It's not a realistic expectation. I am not sure how that comes as a surprise to folks new to orchids . It's not the first time that I have seen an OP shocked that their bloom cycle is ending. I am not wondering if it is the price that is somehow associated bloom longevity. The OP posted more than 2 months ago. The plant may have run it's flowering cycle. Why will the spikes will be cut back to the 3rd node? Whay aren't they being cutt all the way down? I'm asking for my own curiousity, where this information comes from? Is the OP hoping the plant will re-bloom from the 3rd node? It is rare event for a phal in more ideal condtions to re-flower, a Big Box phal even more remote, a sick phal, probably suicide

    The plant needs attention and culture that fits a phal:
    - An acclimation to proper light. A south or East window supplimented by 14-16 hours of light every day

    Temps that are in the 75-80º range day and no lower than 60º night

    A solid watering regime which Richard describes above, not a dip in a bowl of water

    Dispense with misting if there is a problem. The risk of rot is quite high, especially when the plant is underlight. The plant is also risking over-watering. Misting does not increase humidity around the plant. Misting can cool leaves, leave spots, create rot.

    The plant needs time to grow a new set of leaves in proper phal conditons. Then it may reflower for you next year

    Clara

  • astridc
    Original Author
    16 years ago

    Hi Clara,

    I have my basic culture info from the AOS website.

    Now (since the end of September) my phal is at room temperature (70 F at day, around 60 F at night), Nothern light because all my windows are facing North.

    I have started to do what Richard suggested above, I have also cut the spikes all the way.

    I am aware that the flower was near the end of its flowering cycle, but when I was misting it, 2 buds opened beautifully and then the last bud I was speaking about looked ok and ready to open, and when I stopped misting it started to dry and fell off.

    From here the conclusion that it liked misting.

    I will post a picture soon

    Thanks
    Astrid