Cymbidium leaves dying from infection

[rbarata]

Fertilizer is "vitamins" not "food" ... the food, carbs, comes from photosynthesis.

This sentence clarifies a lot of misconceptions I've seen many times here (and not only here).

[Girl_With_An_Orchid]

I didn’t realize the nitro fertilizer was stopping flowers. Gonna stop that one then. I also didn’t realize how low in the totem pole it was. I had been under the impression that it was more important. I know there’s been a dramatic difference for my Phals which have always had good light and water and good enough temp so I figured Cyms would be the same. Here’s an off topic question. When my cyms were still one plant, the bulb on one end would flower and the other end would produce new leaves. Once I split them, the half that had the flowering side would bloom but not sprout new leaves and the other side did the opposite. Thai was the pattern for several years. This year, the flowering side had leaves but no flowers and the other side did nothing. Any idea how to get them both to do both? Or why this has been a thing in the first place?

[Roberta]

The two pieces just need to get bigger. Then you'll have two healthy plants that will do both. Right now you have two small, rather weak plants. (Contrast with the size that it was when you originally got it... when the two little ones become two big ones, you'll have a VERY nice show). They have been inside, so this isn't a good time to put them out... to tolerate low temps they need to acclimate, and be stronger. In the spring (maybe March-ish, sooner if night temps get above 50 deg F) put them outside, move them to higher light bit by bit. In fact, the earlier that you can put them out temperature-wise, the better because you will have a lower sun angle making the transition to brighter light easier. Treat them as the outdoor plants that they really are, and I think you'll have much better performance from them.

[Girl_With_An_Orchid]

From what I’d been reading fertilizer had definitely come across as necessary food as opposed to the supplement that sentence implies. I’m going to have to look more into how to care for my Brassia and Paph. From what I understand they are both less light orchids with Brassias needing slightly more (?). I probably have those wrong too 😅. I’m pretty sure the only ones that are actually in the right lighting is the Phals.

[Roberta]

Depending on which Paph you have, it may actually be right for the Phal conditions. (the ones with mottled leaves - Maudae type - are low-light, warmth-loving) The Brassia may be pretty close to correct too, probably could benefit from a bit more light than the Phals, but most of the hybrids have some warm-growing species in their backgrounds. The Cymbidium is an outlier.. needing high light and tolerating cooler temperatures. Again depending its parentage, it may tolerate a smaller seasonal and day-night temperature variation and still bloom... the ones that are sold in places with warm summer and fall nights may be these "warmth-tolerant" Cyms. All Cyms are warmth-tolerant... they can handle triple-digit (F) temps. But the ones that haven't been bred for the hot muggy nights may not bloom as well or at all without the autumn cool-down at night with warm days. Since yours has bloomed, I suspect it is one of the "warmth-tolerant" types. You just have to get the two pieces bigger and more healthy.

[Girl_With_An_Orchid]

The Paph is a mottled one. It’s a rescue from my neighbor. Not in terrible condition but not the happiest I think and hasn’t bloomed in like a decade. The Brassia is newly bought this year and had serious root rot right off the bat but has new roots growing and a small leaf bundle but no bulb(?). I’m not sure how to make that grow. I think your right about the warmth-tolerance thing. The blooming side has bloomed several years in a row until the recent rot attack.

[Roberta]

Brassia pseudobulbs don't develop until the leaves are maturing. So if you have a small leaf bundle, it has some distance to go (grow). It will get there eventually. So I think the Cym just needs to be grown brighter and with all of the benefits of outdoor air. The warmth-tolerant ones will also tolerate cool (I grow them outside, winter nights can get close to freezing on occasion) but they can grow with much more heat - DirtyCoconuts grows them very well in south Florida. Also outside. So the only time that your Cyms need to come indoors is for the few winter months when you may get frost.

[Shadeflower]

Originally Posted by rbarata

Those are old leaves dying, I think.
I fertilize them full dose in every watering with Rain Mix so I don't think there's a K deficiency.

I've been using Rainmix for the past 8 months. I've come to the conclusion it is not as good as my previous fertilizer.
Long term my cymbs would end up developing brown leaves. Even my fern developed yellow leaf tips.
I have fed that 2 bloom feeds and because ferns are fast growing that has shown the fastest results but my cymbidium has stopped yellowing. It's still too early to tell if it will green up again but nothing is declining and it's winter so it's a bad time to make good observations.

Admittedly on Rainmix alone there was hardly a problem, once I fed just a little bit more Phosphorous for a month did the plants start showing a serious potassium deficiency which I'm in the process of correcting.

I don't think you have anything to lose by trying it one year rbarata, you too for that matter Roberta.

But at the same time I think we have confused Girl_with an_orchid. dying leaf tips can also be fertilzing too much.

To clarify Rainmix is a low bloom formulation so when I talk about using a bloom booster it essentially turns a low bloom formulation into a balanced feed (low bloom + high bloom = balanced)

Most growers use a balanced feed, you can't go wrong with that. Occasionally you might want to add some bloom feed but generally with a balanced feed like 20-20-20 there is no need. It is formulated to have enough of all macronutrients for all year growing.

Some feeds are specially formulated but I am saying they cannot be used by themselves all year long. That's just from my observations. Lots of people are happy using Rainmix as it is. I am not most people. I actively compare and like I said Rainmix is not my first fertilizer. I think it is a great fertilizer to use for most of the year, I've been really impressed with root growth, it's just in autumn something was lacking and by winter by experimenting with different ratio's I created a severe potassium deficiency here myself.

I can show some pictures but rbarata's is arguably the best potassium deficiency example caused by only using Rainmix I have seen.

You can up the strength of the mix as much as you want, if you do not adjust the NPK ratio then the plant will always absorb the same ratio of nutrients but it needs a slightly different ratio at times.


The way I look at nutrients is like fish in a pond.

You have the macrofish. And the microfish. The pond will always be filled with lots of fish, far more than you could fish in a day. If there are an equal amount of Nitrogen fish to Potasium Fish to Phosphorous Fish then every day on average you will end up fishing an equal amount of NPK fish.

Now if you double the fish in the pond what will happen? You will maybe catch a fish or two more in a day but you will still on average catch an equal amount of N to P to K .
Now lets say one day you really fancy lots of K fish and have had enough of N fish, the only way that would happen is if you only add more K fish to the pond.

Now if you fish you will get more k fish on average.

That is why just doubling your nutrient concentration (with Rainmix anyway!) will not work.

If the plant wants more K, you have to reduce the N and P fish or increase the K fish in the pond. Usually there's always plenty of fish in the pond and doubling the fish will increase the catch by a little but it will not change the ratio of fish you are catching so if during blooming the plant want more k fish for a month but doubling the whole amount of fish in the pond will not solve that problem.

Ps: whether one sees Nutrients as vitamins or food is to me irrelevant. I see water, light, air and nutrients all as food. Without any of them the plant dies.

It's irrelevant if you stick it in a dark cupboard or if you water it plain RO water for a few months, the orchid will not survive. So you can argue about light being more important than nutrients and put it all into a hierarchy but at the end of the day if you provide light but 0 nutrients the orchids die. That's all there is to know whether you consider it essential food or essential vitamins. They are essential. That is why they are called as such whereas cobalt is a non essential nutrient.

[rbarata]

I can't argue about fertilization consequences as I don't have control (nor any reliable data) regarding the possible hundreds of parameters that might have some kind of influence in this issue.

Anyway, I can always observe of happens...
The two photos below are from two different Cymbs that are treated in the same exact manner as the previous photos I've posted. The plants are in the same balcony not more than 3 meters away from each other. They are watered with the same conditions. The only thing that might differ is that these last two are more sheltered from the wind. Light, temp, watering frequency, fert concentration, etc are all the same.

As you can see, their leaves' condition are different, they look healthier.