Waterbumps

[orchidbuddies]

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Waterbumps

I have put my orchids in a new greenhouse. I have a space heater with a temp of 65. The humidity is around 70% consitant. I water weekly but today i have noticed "waterbumps" on some of the phal.. What is going wrong? When they came from inside my home they were fine, and here 2 weeks later i have this problem.

[lyn]

Does your local Agricultural center offer any testing? I have never heard of this! Let me know what it is if you find out. I have been lucky so far using Thiomyl, Physan, RD20, Cinnamon, Antibacterial Dawn, Pyroxide and for scale and ants safers soap. Good Luck!

[Ironwood]

This sounds like Odema to me. Taken from AOS Guide: Orchid Pests and Diseases.

Odema This physiological disorder that occurs occasionally on orchid plants is more cosmetic than harmful. It appears as small watery blisters, usually on the underside of the leaf, but can occur on both leaf surfaces. In severe cases the blisters may rupture. Over time, the blisters will heal as cork-covered bumps and remain as long as the leaf is attached to the plant. Oedema occurs under certain climatic conditions wherein the roots take up moisture faster than it is lost by the leaves through evapotranspiration. This excess moisture causes cells in soft tissue to swell and form external blisters. Aside from unsightly leaves, no real harm is done to the plant. Even in severe cases, where the underside of the leaf is completely peppered with small blisters, the leaves remain on the plant. It is more apt to occur in spring or autumn.

Also see this site.
Oedema Factsheet

[lyn]

That was some awesome information! I loved the link that explains oedema in detail! I have never had this problem but we are building a greenhouse this summer so this is good to know!Thanks Lyn

[orchidexpress]

are they staying too wet? Water bumps could possibly be a fungus. Send me a picture so I could help you to diagnose your problem.

Lee
Orchid Express & Leasing