Ok to cut off a phal leaf?

[greenpassion]

Hi all. I have a small collection of phals, (22) and one of these has a leaf that is off color, redish with marks along it's underside. I would take a pic but the camera on my phone keeps saying 'camera failed' each time I try. Anyway, I am going to treat with physan 20, but I also feel the leaf should be removed. I don't think it's insects, I suspect it's a fungus or some other disease. My question is can I just cut it off, or will this harm the plant. It's not a new leaf-it's one of the large ones close to the bark. Other than this leaf issue, the plant is very happy. Lots of new root growth and recently a new leaf. I grow these in a bark mix under led lights, on a heat mat. I feed MSU fertilizer for well water. Of the 10 on this shelf under lights, 7 are spiked and bloomed. I've just never had to cut a leaf off a phal before, and need some reassurance

[jkofferdahl]

Well, you CAN cut the leaf off, using sterile blades, and then seal the cut with cinnamon powder. That works. Don't do it yet, please.

I'd really like to see the leaf and the plant. You're contemplating a drastic step. Visuals help a lot, but maybe some more info will work. A lot could be going on here. Is it the leaf underside that's reddish but the top is still green? A lot of Phals have reddish undersides on leaves, and sometimes when a leaf is sluffing it can take a reddish tone as chlorphyll leaves the leaf. Or is it the entire (both sides) leaf? That could be a sign that a lower leaf is simply being sluffed by the plant as it grows the new one you mentioned. Is the leaf squishy/spongy or is it firm? If it's softer than the healthy leaves it has a fungus or bacteria. Cut it off yesterday! Spray with Physan 20! I'd even consider an exorcism. My guess is that the leaf is simply sluffing as the new one comes in, and it'll eventually yellow, brown, and drop off all by itself.

[greenpassion]

Ok, in looking at this phal, it's more than one leaf, and it's the top of the leaves that are discolored, with a sunken black splotch with yellowish edges on it. The other leaves are also beginning to take on this appearance, but it's mostly on the edges of the leaves. Will spraying the plant with physan 20 get it back to health again? The root system is great, and it just put out a new leaf. On another issue, I also have some phals that have little pitted like pock marks on the leaves, and what almost look like scratches in random areas of the leaves. If they had scale, wouldn't the marks be raised, not pitted? I just ordered the physan, and when it comes, I plan on wiping the whole area down, cleaning everything-trays, the glass panel they are on, etc. I don't know what else to do. To be honest, these problems aren't exactly new. I just didn't think that they were serious problems until I noticed these marks and discolorations spreading.

---------- Post added at 02:12 PM ---------- Previous post was at 01:54 PM ----------

I also have read of people soaking the phal in the physan 20 for up to 30 minutes. Should I do this? or just spray the leaves? I wish I could get pics of these problems. Need to get to US cellular and get the ability to take pics again!!!

[jkofferdahl]

I wouldn't soak the plant, but I'm not a soaker. I don't ever soak. In this case, soaking would be severe overkill.

Scale is a different animal, and something you want to attack right away if you have it. Scale appear as small, hard, brown lumps on leaves, and can be pretty easily picked off with a fingernail. If you find it, clean your orchid from top to bottom with rubbing alcohol, spray with systemic insecticide, and get a Priest to exorcise the plant.

The random scratches could be just that - random scratches. How large are the brown areas on the leaves, and are they of the same consistency as the rest of the leaf, or are they softer? It's possible that temperature has played a role here - Phals far to the warmth-loving side can show discolored leaf areas when grown in cooler conditions.

[bil]

Sounds like something I get if during the night in the winter condensation drips onto the leaf, chilling it.

I just treat it with mancozeb, an excellent fungicide, and sometimes the leaf survives, and sometimes it dies. If it dies remaining dry, (which is usually the case) I leave it to die naturally, if it were wet mould, I would cut it off.

[rbarata]

A photo could be the difference between a good and a bad advice.

[Sharon's Sheepdogs]

Reddening of the leaves can also occur from too much light or a magnesium deficiency especially if the phals were exposed to cold temperatures. Are either of these a possibility? A photo would definitely help.

[greenpassion]

Thanks all for your replies. Again, I am unable to use the camera on my phone, and at the moment have no way to get a pic posted. That said, all of the phals I have under my lights are on a heat mat, so being chilled is not an issue. I live in Vermont, keep my house at 63./65, and the heat mat is always on. Warmer thru winter, and low to off thru summer. This phal has had this strange colored (redish) marked leaf for possibly over a year now with no change, so I didn't think of it as a real problem. But now as I said earlier, it's spreading to the other leaves and seems to start on the outer edges of the leaves. The new leaf it just put out is fine.

[estación seca]

A lot of Phals get reddish leaves when exposed to good light. It is not a worry at all.

The depressed marks you describe are commonly seen in Phals kept too cold, or with mechanical damage. Once a leaf of any plant has damage, it will not return to normal appearance. The plant has to grow new, healthy leaves.

Your house is very cold from the perspective of a Phal, even with bottom heat. They will just barely survive temperatures like that, and probably won't grow well. I would expect to lose some each year with temperatures like that. They are warm growing plants.

Physan is unlikely to help your plants. When stressed they are very prone to fungal infections, and antiseptics won't help with that.

There are many really beautiful cold to cool growing orchids that should do well for you. Look at Masdevallia, Dracula, Pleurothallis, Odontoglossum, and New Guinea Dendrobiums.

[greenpassion]

Ironically, my phals are all doing incredibly well aside from this one with the leaf issue. I now have 7 fully spiked with up to 15 flowers on each one. My mini phals as well as my regular sized phals are all growing new leaves, and new ariel roots with big swollen tips. I've never had a better spring with these. Many are over 4 years old, so the temps seem to really be fine for them. Since I changed my fertilizer over to MSU things have just exploded here. Just got a link from a member who posted pics that look just like my issue.

---------- Post added at 10:44 PM ---------- Previous post was at 10:40 PM ----------

Tomorrow Ill post some pics I'd taken of my collection when the camera on this phone worked. They are really something to see!!