Micro orchids reddish/purplish tinting, yellowing, decline; otherwise flowering..!

[BingPot]

Hi,

I'm seeing reddish/purplish tinting on my Schoenorchis, Sophronitis and Trisetella, some yellowing in many plants in the top 1/3 of my vivarium, and some general decline in some species as evidenced by some premature leaf drop/decay vs. new leaves.

I started tweaking the light intensity from 95% to 70% to see if excess light is causing the discoloration and/or general weakening of the plants over time (maybe too much light = too stressful), despite good flowering seen so far. I am holding fertilization, temp and watering fixed while I do this so as to try to isolate factors, but I suspect some of my problems are affected by multiple factors?

Any suggestions/advice, general or specific? Thanks in advance!

Background (vivarium pic attached):
After years of research and slow building/acquiring, I've been keeping a wide variety of mini/micro orchids, ferns, epiphytes, etc. for a little less than a year now in a dedicated 12x12x18" viv, and I'd like to start getting more serious about fine tuning the growth parameters like light, fertilization, temperature, etc. to help keep everything growing well and optimal. I did try to select only species that have a similar temperature and humidity requirement while allowing light and air movement requirements to vary because I believed I could provide variations in those two via purposeful placement of each plant. I have gotten many of them of different growth profiles to flower over the last 3 months; so I believe they're relatively happy, but given some general weakening, early leaf drop and/or varied pitting/scarring/discoloration in the leaves with a good number of the specimens, I still have some work to do. Some plants are mounted, some are "potted" in the hardscape with ample drainage (hidden holes) and media that suit their requirements.


- Light is on at 95% https://froskr.com/lighting/skylight-tiny-rv/
- Small 5V fan provides a range of moderate to minimal air flow throughout based on positioning of fan, hardscape dynamics and plant positioning
- Thorough hand spray the plants liberally once daily (may skip once or twice a week depending on if the upper plants look too wet)
- Fertilization with 20-30% of recommended concentration for orchids (using Better Gro, Orchids Plus)
- Enclosure is ZooMed type with venting in front, bottom and rear, upper corner (small opening in rear to keep humidity high)
- Temp evening lows 65-68F and daytime highs 74-76F
- Humidity 60-80%

Thanks in advance for your time!

[BingPot]

IMG_1144-big.jpeg - Google Drive

Not sure if a Google Drive links work for embedded images or as a link...? Didn't know jpg attachments had to be so small; trying a bigger one of my viv...

[estación seca]

Welcome!

I'm guessing it's due to high light. Orchids change slowly.

[Shadeflower]

Hi Bing,
I like your setup. It looks really healthy overall.

I can see the plants you are concerned about and they are all very close to the light.

You are not the only grower in such a predicament. If you dial the light down you risk the lower ones not getting enough but at the moment the top ones are getting slightly too much.

When it comes to fertilizing the best we can do is try little tweaks and see what works better. I have made some observations but haven't really figured things out well enough to give concrete advice on fertilzing.

If it helps I will share my observations. Better gro is one of the better orchid fertilizers but it does contain too little Calcium and Magnesium for orchids.

You will want to add cal-mag if you use better gro.

Do you use tap water or rain water? That makes a difference how much cal-mag to add but you should definetely add a bit of magnesium if your water has enough calcium. I would suggest for every gram of better grow you add 0.2-0.5 grams of epsom salts.

Or if using rain water 4 ml of cal-mag for every gram of better grow.

That is what I would do.

Mini's will benefit from micro nutrients a lot. Their demand for macro's is low but it is easy to feed too little micro's imo.

So my recommendation would be to add like 2ml of Canna Trace mix per gram of better grow

or add 10ml of seaweed extract per gram of better grow. Seaweed is quite weak but never exceed the recommended dose. I'd even never exceed half the recommended dose.

Hope that helps a little.

[BingPot]

Thanks, estación seca (love your signature quote, btw)

Thanks, Shadeflower, for sharing your observations re fertilization. I will start experimenting with adding some additional micronutrients. I had no idea re Better Gro being relatively low on micros (for micros). I thought I could get one fert formulation and be done with it for all orchids (surely wouldn't be complicated like dosing for aquarium plants, hobby of a distant past for me ), but it makes sense that micros might need something slightly different from the larger varieties.

I use RO water; so looks like I'll have to revisit the epsom salt AND CaCl additives from my old aquarium box. Do you have any idea how much Azomite powder I could add to my watering solution? I have quite a bit left from my days of vermicomposting too...

Thanks!

[Shadeflower]

hi Bing,
I know I wish it were easier. Why can't one company just bring out the perfect mix...

Like I mentioned better gro is imo one of the better ones!

But with it being designed specifically for tap water using RO water will cause calcium issues long term. There is no if about it, just when.

As to the micro's, again better gro is one of the better ones(contains double the micro's to Rainmix for example). But like I mentioned for mini orchids you want to dose them low. When doing this you will be feeding a very low dose of micro's . I swear by adding more micros's for them. It's your choice if you want to try it or not.

here is an article explaining it in more detail if you are interested Why You Should Foliar Feed Orchids (& How To Do It Right)

ps: that article recommends foliar feeding and I also believe it works great but I generally don't have the time to foliar feed all my orchids so I add it to my water in the dose specified above.

I have never tried azomite. The problem is it's organically sourced. You might think this is a good thing, generally gardeners want organic.

But in orchid growing I came across a study suggesting orchids prefer non-organic especially in winter as the organic needs to break down to be absorbed a lot of times. Apart from this slight drawback which might or might not even be an issue because it is organically sourced and not made in a lab is that it contains considerable amouns of toxic heavy metals like lead, mercury, cadmium and arsenic. ORchids are more sensitive to these metals than other plants so I'd avoid the azomite myself.

Who knows you might do more damage than good using it. I'd be cautious with that. The calcium and magnesium is needed 100%, the micro's might be beneficial but are not an immediate requirement.

[thefish1337]

Originally Posted by BingPot

Thanks, estación seca (love your signature quote, btw)

Thanks, Shadeflower, for sharing your observations re fertilization. I will start experimenting with adding some additional micronutrients. I had no idea re Better Gro being relatively low on micros (for micros). I thought I could get one fert formulation and be done with it for all orchids (surely wouldn't be complicated like dosing for aquarium plants, hobby of a distant past for me ), but it makes sense that micros might need something slightly different from the larger varieties.

I use RO water; so looks like I'll have to revisit the epsom salt AND CaCl additives from my old aquarium box. Do you have any idea how much Azomite powder I could add to my watering solution? I have quite a bit left from my days of vermicomposting too...

Thanks!

You can get an orchid fertilizer that does it all and has cal mag + micronutrients quite easily:

MSU (RO)
Dynagro Foliage Pro
Dynagro Orchid Pro
Klite
Jack's LX/Jack’s Professional ORCHID-RO

all of these are complete fertilizers and will work when applied at dilute rates for your plants and contain everything- no need to buy multiple products and entertain complex theories about orchid nutrition.

either way it looks like your plants are getting a lot more light than they need at the top, everything in the lower section looks super healthy. fertilizer might help them deal with the higher light levels but you can always raise the light a bit and see if that helps too. like ES mentioned it may take a couple weeks to a month to see how your orchids respond.

[Roberta]

Originally Posted by thefish1337

You can get an orchid fertilizer that does it all and has cal mag + micronutrients quite easily:

MSU (RO)
Dynagro Foliage Pro
Dynagro Orchid Pro
Klite
Jack's LX/Jack’s Professional ORCHID-RO

all of these are complete fertilizers and will work when applied at dilute rates for your plants and contain everything- no need to buy multiple products and entertain complex theories about orchid nutrition.

either way it looks like your plants are getting a lot more light than they need at the top, everything in the lower section looks super healthy. fertilizer might help them deal with the higher light levels but you can always raise the light a bit and see if that helps too. like ES mentioned it may take a couple weeks to a month to see how your orchids respond.

Given that orchids need very little fertilizer (and the micro orchids even less) I'd agree that other factors (such as light) need to be considered first. And then be patient to evaluate results - orchids don't do anything fast. Ask 5 orchid folks about fertilizer and you'll get 8 opinions... and a lot more heat than light.

[TZ-Someplace]

Yellow and red sound like too much light overwhelming the sugar movement mechanisms in the leaf resulting in the leaf getting rid of chlorophyll to adapt by lowering production and by boosting anthocyanin red pigment to protect/shade. Magnesium can help that by increasing the amount/efficiency of the enzymes used to move the sugar into the vascular system, which is different than making chlorophyll, although it will also help make chlorophyll when that is needed.

I would try fertilizing at least once with Epsom salts at 50% max fertilizer strength (a little more than your normal 30%) for a simple fix. It is difficult to "over salt" with Epsom salts so even doubling fertilizer max shouldn't hurt the plants. Plants can store the magnesium from a large dose, and it you don't want to mix it in water with other fertilizer ingredients.

You can submerge and soak the plants if you want. Magnesium can be taken in through the leaves, iirc.

[Shadeflower]

I know for a fact that I have killed orchids not feeding them correctly.

I also recently pointed out that MSU is the worst feed I have tried on my orchids so far.

ask 8 people and they will have only tried one fertilizer and have no idea what signs to look for to give an indication one is better than another.

Did the best growers do hours and hours of research and observe their plants to get good results?

Can you grow orchids doing no reseach? Of course, that is the beauty of them.

What about seedlings? Success rate will seedlings will drop considerably using MSU and I will stick by that statement!

The fish, do you use kelpmax , inocucor, seaweed extract, and quantum total yet you say what you feed is not important.

So why bother if it doesn't matter?

This argument is defunct really because Roberta you will never grow seedlings and never change your mind.

I know how important the right nutrition is for seeedlings in articular, the older they get the less important and more tolerant they become.

seedlings on the other hand can either have a 100% success rate or less than 50% .

The good nurseries know this.

Ok so maybe not too critical to an orchid hobbyist but it is stil lrelevant, a hobbyist will not achieve more than 50% with MSU.

So maybe it doesn't matter but it does if you want to achieve 100% with seedlings.

I can see why some people don't care and losing a few plants a year to infections is an acceptable loss.

I know the right people will value my comment for what I am saying. Who wants to lose 50% of their seedlings if it can be avoided.

But at the same time it is easy to not think about it and also be able to get good results without thinking about it. Still that is like saying a child can be fed on mcdonalds every day for the rest of its life and be completely healthy by the time it reaches 18. It would be practically impossible. Mcdonalds is very unhealthy.

I'd advise people to think otherwise to watch supersize me.

Millions would disagree and say mcdonalds is great. Same point as the orchid nutrition. Maybe feeding whatever works great. Not disputing it but the orchids will not be as healthy after 10 years and seedlings won't even make it a lot of times.