Cattleya rot

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Angela,

I have grown the odd Catt indoors in clay pots and they did ok.
The root growth was good and they are definitely more forgiving of any slight overwatering.
It’s something I may try in the future but to source 60 clay pots of the appropriate size would be quite an undertaking,

David
 
Especially clay pots with holes or slots in the side - I looked for them and, short of getting them commissioned myself from a pottery, the nearest place I found was in Belgium!
 
What you do is buy clay pots and drill holes or slots in them. Ain't hard. If you break one
now and then, you've got pottery shards for drainage.

I did consider that but baulked at the idea so settled for an inverted net pot in the bottom instead which seems to be working ok for the three hybrids I have!
 
Just getting back to the original photo at the beginning of the thread ------ the leaves are relatively light yellow-green ..... chartreuse coloured.

Were the leaves always like that in colour? Or did the leaves start out as darker green, and then fade to this colour, followed by the rot?
 
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Sorry but it went to orchid heaven soon afterwards!
Hopefully this episode has improved my culture and there won’t be any more deaths due to poor culture,
David
I think you had good culture the whole time!

Now problems arises and you corrected them. It’s ever ongoing even with me.
 
Thanks Leslie,
the pots in planters were sat on stones all the time. It’s just that occasionally the water would come above the stones in summer when I watered more often and I didn’t notice. Now I know better!
 
MM ------ as this thread has the title of 'cattleya rot' ----- I will mention some nice things that give all orchid growers confidence/hope in orchid growing. I haven't had a catt rot or even die in over a few decades of catt growing. I have lost a total of 4 catts though ----- but this was back when I first started orchid growing. That was when I was a newbie. But learned some important things from that - which amount to just a short list of tips ----- quite short. And sticking permanently to the basic tips definitely helped me have no issues - zero issues.

Although ----- I did inadvertently scorch a few catt leaves during peak sun scorching conditions - for some of my sun-hardened catts, but was not life threatening. All under control.

One main thing I stick by is to try make conditions tough for whatever unwanted organisms might/could grow inside the pot and/or in/on the roots ..... and also on the leaves and stems.

The way I water - is by sending most of the water into the media toward the outskirts of the pot ----- have the water flow into the media toward the sides of the pot. Pretty much like a waterfall cascade down into the media - the region along the walls of the pot. The media there gets very wet, but a dry gradient toward the centre helps with water movement and evaporation and humidity within the pot (or that's what I reckon anyway). My pot is wide enough so that the media in the whole pot doesn't get water-logged/saturated when I do the watering. The roots of my catts are generally regular ones ----- the ones that are not adapted to watery growing conditions.

I put much less water toward the centre of the pot ----- and sometimes none. The roots sometimes need to get their nutrients, so I figure that they at least sometimes need to get slightly wet in order to pick up whatever is still hanging in the media (like fertiliser, mag-cal etc). I apply 'weak' fertiliser and mag-cal ---- just once a month.

I do watering generally each morning. But watering every morning is not actually necessary. Even in very dry conditions, I've had somebody help me with manual watering (spray wand) with 2 days of no water. I just like to get in there to do the watering each morning - which allows me to keep an eye on all my plants ------ just to make sure they're all fine.

Sometimes - I allow the media to just dry out - including the roots, which probably does make things tough for certain unwanted organisms that might want to do their stuff inside the pot and in/on the roots. I just so happen to grow all my catts in scoria. I'm sure that I could grow bark or bark/perlite mix too. But I just use inorganic media in my tropical conditions.

Natural and gentle air-movement is good in the growing area. The air moves around the leaves and stems and all, and down through the media in the pot. My pots are all good drainage ones - sitting on drainage grates, that prevents the pot bases from sitting in any drained water. The drainage grates also allows all holes to get air into (and out of) them.

The temperature is generally quite nice for the orchids, and the roots are never watery and cold for any lengthy period of time.

So after a few decades plus ------ zero issues -- no losses of any catt, and no rot. But I did have a dendrobium beetle chomp a flower spike in half and even take out a catt leaf this season ------ but dealt with nicely by using carbaryl.

So for orchid growers out there ------ when the growing conditions are continually kept satisfactory ----- continually ----- the orchids can really do what they're supposed to do - grow nicely and healthily indefinitely. If the nursery growers at orchid nurseries can grow their plants really well, then so can us home grower orchid fans.

Although - I do have the benefit of tropical conditions here, which cuts down on a lot of effort, as compared with snow country conditions etc. But the same thing applies ------ aiming for continued satisfactory conditions for the orchids to grow.

I'm also posting this because your orchid didn't make it due to rot. So just mentioning a little about what I do for my orchids at home ----- so could possibly become useful to somebody else too. Each grower has their own ways of doing things. We just pick and filter and eventually all come up with a system that works well for very long times.
 
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Southpark,
thanks for the information.
It’s so interesting to hear how different people grow their plants in different parts of the world. The beauty of the internet and this forum.
If I were to water my catts every day they would all be dead in 6 months, but in your tropical conditions it works very well.
Stephen Van Kampen on YouTube has some interesting videos and also waters his catts every day and they grow very well. But he is in Texas where the summers regularly top 100 degrees f.
I take your point about watering around the edge of the pot. This is where most of the Catt roots end up after a year or so anyway so watering there makes a lot of sense. Avoiding waterlogged compost especially when you have bigger pots that take longer to dry out is critical.
 
Most welcome David! Sure is ------ this is a fantastic feature of these orchid forums, where we can discuss the various setups we have. I think it's great how you're beating the issue by quickly acting upon what you saw ----- and you most likely have everything sorted and under control. You have an ouststanding orchid collection - along with the other members here. Also fantastic how you guys (and girls) in USA and Europe just import the wonderful orchids like that.

I haven't tried before, but I expect a long and expensive road (and probably risky too - as in orchid not making it through the trip and quarantine/fumigation etc) to do that sort of thing in Australia ----- importing orchids that is. It's probably expensive to do in USA and Europe too ----- but just guessing more do-able than in Australia.

Thanks David --- for mentioning SVK. Totally agree with you! He does make interesting and very good videos on youtube. I watched some of his catasetum growing videos, and his cattleya growing ones. The videos are presented really well.

True! The catt roots eventually gather and build up along the wall edges. Absolutely agree with you about undesirable water-logging of media - which can be easy to do in large pots with lots of water just dumped everywhere into the pot. The root-drowning slurry mix can be deadly for sure! The edge watering is one way to get around some issues. And another way is to use shallower pots (readily available) ----- and the edge watering also works very nicely for shallow pots too. But the grower also has the option to water the whole media too ----- depending on their own situation and growing environment. Some nice flexibility there.
 
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I’ve probably lost about six plants over the course of this year to this form of rot. It’s fairly slow to develop but eventually kills the plant. It usually starts on a new growth, often as the bulb is developing. We are fairly low on chemicals In the UK compared to others. Anybody hazard a guess as to a cure? All I can do at present is cut the plant rhizome as soon as I see it but it rarely stops it. The rot seems to have travelled through the plant before symptoms develop.
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David
Benomyl, Benlate, Fertilome Halt!. Worked like a charm when there were still some live roots on my Cattleyas to absorb it. I didn't do any cutting until at least a week, to give it time to absorb this systemic fungicide through all the living tissues. The only place I see it for sale now is on the island of Bermuda.
Banrot is very effective, as well. So is Subdue, but you'd have to mortgage your house to afford it. Air movement, i.e., gently wafting air, is best preventative. Watering only early in the day, to let it get as dry as possible before nightfall, helps a lot, as well.
Oh, yeah. There was ONE bad batch of DuPont benomyl that caused plants to die very slowly. Symptoms were described as "orchid AIDs". Proved that "a little knowledge is a dangerous thing", since everyone stopped using it after that ONE SINGLE bad batch.
 
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