Leaf Problems?

[Carper]

Paph PEOY x Susan Booth

I bought this mature seedling from In Charm orchids in Taiwan in June and it has grown very well, producing a new growth and a healthy root system aswell. However, I have lost one leaf which turned yellow and "veiny" from the ends until it finally died. Now, the remaining 2 larger leaves are also turning. The plant is probably approaching flowering size now but may not get there at this rate. I use MSU, at a low strength during winter with only a small amount of epsom salt supplementation occasionally.

Any ideas, as to the cause, ie iron deficiency etc or recommendations would be greatly appreciated.

Thanks

Gary
UK

 

[SlipperKing]

This can be tough Gary. The sunken areas are from dehydration. The yellowing ..humm all I can add is increase you Ca and Mg as Rick has been preaching to all of us. I use to have a lot of yellow leaves on everything but not anymore. The greenhouse is much brighter then in the past but the plants are medium to dark green because of the lower K and hight Ca/Mg. I swear by it!

 

[Stone]

Paph PEOY x Susan Booth

I bought this mature seedling from In Charm orchids in Taiwan in June and it has grown very well, producing a new growth and a healthy root system aswell. However, I have lost one leaf which turned yellow and "veiny" from the ends until it finally died. Now, the remaining 2 larger leaves are also turning. The plant is probably approaching flowering size now but may not get there at this rate. I use MSU, at a low strength during winter with only a small amount of epsom salt supplementation occasionally.

Any ideas, as to the cause, ie iron deficiency etc or recommendations would be greatly appreciated.

Thanks

Gary
UK

Hi Gary, It doesn't look like an iron problem to me but its hard to be sure. A quick way of checking for Fe deficiecy: Take a sample of some of the bark in the middle of some of your pots and check its Ph. if its around 7 or under, its very unlikely to be Fe deficient.
Finding the exact cause can be difficult. How's your humidity? What is your water like? Temps? It doesn't seem to be pest damage either.
You need to consider one thing at a time. Lets see what the others think.

 

[Shiva]

How about ethylene? I don't know where you live but if you started to heat your house or g/h with gas, there might be enough ethylene produced to cause something like this. Just a thought!

 

[Carper]

Thanks for your replies.

Rick,

I have just started to use the extra calcium and magnesium with lower strength MSU but as its our winter and the days are extremely short, theres not much growth happening at the moment. I don't want to feed high now as I've only just managed to stop my erwinia problem which I think may be caused by high nitrogen!

Shiva,

I use a 3kw parwin heater only, so no problems in this area.

Stone,

I use the orchiata bark and its reading about 6.8 and most of my plants are just going mad in the stuff! I have a very powerful extractor fan which refreshes the air in my modest 3m x 3m greenhouse in a few minutes. Humidity is around 70%, temps are 13C min at night and 20C in the day. Water I feed is RO and I wait until its the room temp of the greenhouse which averages about 17C.

Thanks

Gary
UK

 

[Orchidzrule]

Gary, after reading your culture technique, it's clear you really do know what you're doing, and after reading I would bet on it being a deficiency of some nutrient. My gut feeling is also lack of Magnesium and/or Calcium, as already suggested. While iron could be lacking, it looks as though your youngest leaves are in better shape than the older ones--iron deficiency usually results in the opposite pattern.

 

[JeanLux]

...I use the orchiata bark...Gary
UK

Hi Gary, where did you grasp it? Last time I mailed the producer they were sorry, but not distributing it in Europe !!? Jean

 

[Roth]

I got the same problem on many multis from Taiwan ( and I am not alone, some other growers reported the same). Apparently it would come from their nutrition schedule.

It has nothing to do with excess/deficiencies of anything apparently, but more an additive that they were used to but that we do not use. Honestly, I have lost quite a few plants from that, at least they had the setback of their life. That's why too I avoid to buy plants from some growers in Taiwan, though the plants are very well grown, I can never get them back on track.

I got that chlorosis/dry leaf look style. You will most likely loose all the leaves Made in Taiwan, but the plant will grow OK from now onwards.

Some growers are using a drip system to water their plants, with amino acids, etc... and when you move the plants out of that, it is a mess.

I got a batch of very big multis at the TIOS this year, many developed water soaked blisters as well on their leaves, that go on and off, and they are never as strong as the plants I get elsewhere.

 

[cnycharles]

if they are using a drip irrigation system in taiwan (the possible suspect vendors), maybe it's also the problem that the old roots have developed with lots of moisture around, and not being grown 'dry' the roots and plants are not happy. one of my information sources (either here or orchid club, hard to keep track) pointed out that roots that grow wet like in hydroponic, semi-hydro or drip are used to that (maybe it was a constant flow hydro table), need to be kept in that watering system or else they have problems when you take them out

 

[Carper]

Thanks for your replies everyone. I have began to supplement the lower strength feed and with calcium and magnesium so will see how this goes for a while. My feeding regime does normally get the plant to produce stronger healthier leaves etc after a few months, so I hope I can grow this one on from the new growth and possibly get the main to flower before it gives in!!

Gary
UK