Cattleya roots dying suddenly

[mam288]

This is my set up.

[SouthPark]

Originally Posted by mam288

it sounds like people have had luck with lava rock, so I've got some on the way and am going to see how it works for me. I'm excited to try it!

MAM ------ orchid growers very successfully use various kinds of media. They usually work out a strategy for watering etc based on the media they use, and the pots they use, and taking account of the environment (humidity, temperature, air-movement etc).

Lava rock does indeed work nicely in the tropics. Some long time growers favour lava rock (aka scoria). I have lots of highly experienced orchid grower friends that use anything ranging from from sphagnum moss, to plain fresh-water river pebbles, and rocks, all the way through to bark/perlite mix, or bark/perlite/foam mix.

Once a grower gets their recipe (which includes the whole lot .... hardware and watering strategy) working nicely for their own growing area ...... they often just stick to it if it works very nicely for very long amounts of time.

Considerations sometimes need to include number of orchids being grown, and how much time/effort is needed to water each one or to add nutrients to each one. So techniques can vary. Techniques can also involve automation. Eg. automated sprinkers, automated fans, automated heating etc.

It does take some time to get sorted. But we all usually get there. It's a nice learning experience.

Originally Posted by mam288

This is my set up.

Good setup MAM. Good setup.

[mam288]

Originally Posted by SouthPark

Also ----- digging into the media of 'control' pots during 'trial periods' (with no orchids growing in those pots) ----- can allow you to see if the media dries out too quickly or not. Drying out for long times can be no good too ..... since orchids need enough water to function properly.
[/B]

SouthPark - I love this idea and I'm definitely going to try this! Also, thanks for the watering video, it's very helpful to see it demonstrated. You have a beautiful collection of plants

[SouthPark]

You're most welcome MAM! Once you get to know roughly what the media will be like in the control pots ...... you will eventually know just how much water to apply (and also when to apply) - and there-after you will probably not need the control pots anymore.

Excellent work with that orchid platform that you use.

[mam288]

SouthPark - Thanks!!

[mam288]

Help! I am need of your orchid growing wisdom again!
I seem to be having the same issue with another plant. It's a cattleya very similar to the one I started the thread asking about. It's potted in bark and was repotted last May. The leaves look healthy and there is new growth but when I went to water it today I noticed there was moisture in the lower part of the pot. I unpotted the plant and it looks terrible! The roots look burned and there was one long root that looked like it was about to rot. It had definitely put out new roots since repotting but the new roots are dying. I think it's basically what happened to the other plant. The other plant had progressed to the point where the roots were just completely rotten and I couldn't see the burning (if that's what it is) I'm seeing on these roots. I have a few possibilities but am hoping someone here can help me figure out what is going on!

My thoughts are:
1) Root rot from too much moisture. I've been watering it about once a week and the top always looks dry. Except for today I haven't noticed moisture in the lower part of the pot. It obviously has not been drying out all the way down. Could it just be that the bark at the bottom of the pot is staying too moist? If so, if the top is dry how do I tell if the bottom is still moist. The top layer is dry to the touch and I sometimes stick my finger a little bit in and don't feel moisture. I obviously need to check deeper but then I'm disturbing the roots and media?

2) Fertilizer burn. I'm thinking this is likely it as the roots look burned and I just realized I'm not using one of my additives at the right frequency. I'm using Dyna-Gro Orchid-pro liquid plant food 7-8-6 at 1/2 the recommended concentration weekly. The instructions say to use 1/2 tsp/gallon with every watering and I've been using 1/4 tsp/gallon every water with one week a month flushing with just water. I also have been using First Rays KelpMax liquid seaweed fertilizer. When I read the bottle today I realized I'm using it too often. It says 1 tbsp/gallon once a month and I've been using it weekly at 1 tbsp/gallon except for the monthly flush with water. I thought the liquid seaweed was separate from the fertilizer but should I be considering them as additive and lowering the concentration/alternating instead of using them together? Could too much liquid seaweed cause the problems I'm seeing?

3) I use tap water to water the plants. Could it be the chlorine or minerals in the tap water causing the problems?

Since I caught this plant earlier I'm hopeful that it can still make it. I repotted it in lava rocks for the moment. Does anyone have thoughts on what might be the issue?

[estación seca]

You are not watering your plants often enough. I don't know how I can be more clear.

[SouthPark]

Originally Posted by mam288

but when I went to water it today I noticed there was moisture in the lower part of the pot.

My thoughts are:

1) Root rot from too much moisture. I've been watering it about once a week and the top always looks dry. Except for today I haven't noticed moisture in the lower part of the pot. It obviously has not been drying out all the way down.

mam ----- hi there!

There appears to be discrepancy or contradiction between "have not noticed moisture in the lower part" and "obviously has not been drying out all the way down".

Just to clarify ------ are the roots very wet and soggy and mushy and rotting in the very wet region?

If roots are very wet toward the deeper depths of the pot (such as toward the centre of the pot), then just try repotting the orchid in pre-wetted (but not soggy) bark ...... and then ...... when you water ..... you can put most of the water down the sides of the pot, and less water toward the centre.

And you can water more than once a week if you like if you do it that way.

Alternatively, you can use shallower pots.

However - in the tropics, I do have one of my favourite cattleyas growing in 100% scoria is a very large pot. Very large pot. But its roots don't drown or rot when I focus most of the water down toward the sides of the pot.

I think of 'waterfall' with this watering method. The water keeps media toward the sides of the pot quite wet - and it allows the inside of the pot to stay nice and humid enough --- and not drown roots toward the middle of the pot. The roots that grow out to the sides tend to become quite hardy and used to the wet region too.

[mam288]

Southpark- to clarify, I saw moisture today but usually it looks dry and this is the first time I've seen moisture like that. I just meant that today the bark was quite wet and definitely hadn't dried out which makes me think that might have been the case before except that it wasn't so visible.. The roots were firm, not soggy, but they were dark and looked like they might start to eot. Does this clarify things? I have been trying to water around the edges since your response last time. Maybe the damage had already been done? It sounds like you think it's more of a watering issue than the amount of fertilizer?

[SouthPark]

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