Yellow and more yellow...

[OrchidIsa]

Can anybody help me with this one? My niveum and tigrinum are getting some yellow... The first gets it on bottom leaves but on the upper ones too but the tigrinum is always loosing the bottom ones.

Tigrinum


Niveum

 

[Happypaphy7]

The first one, if the yellowing stops there, then I don't think it is something to be concerned about. Natural aging.

Niveum does look like it has some trouble.
When did this start looking like this?
Is this new?
I think you might want to check the roots to see if there are any alive.
Yellowing from the leaf tip on many leaves like this can be an indication of poor roots.
If the roots are good, then you can think of repotting. It could be chemical related.

 

[OrchidIsa]

The tigrinum is always doing that. I think that's the fourth leaf yellowing and diying... As you can see, there is another one beggining too... I had that plant for a bit more than a year.

The niveum has great multiple roots. I just repotted it a few weeks ago. Everything looked okay. It was like that before repotting and the "adventure" continues..!

 

[Stone]

I would put the tigrinum in a smaller pot or place some styrofoam pieces in the pot so it dries fast. Tigrinums seem to like a very quick wet / dry cycle.
The niveum, If you have been keeping it less than 18 or 20C it is probably asleep. I would just try to hold it steady until it starts to move before trying to feed it or whatever.

 

[Bjorn]

Agree, there is something wrong with those plants. Perhaps not serious but.....some sort of deficiency?
Mike, I might disagree slightly about tigrinum needing a quick drying. At least during summer season. Quick drainage, yes, but not drying. The region from which it comes, or used to come, might be extinct there, is in the middle of the monsoon during summer, nothing gets dry there......but agree, as a general rule, underpotting is usually better than overpotting except for some special cases.

 

[John M]

What are you feeding them, Isabelle?

 

[Ozpaph]

If the roots are OK, then I'd use regular dilute complete fertilizer with intermittent 'seaweed'. That should take care of any 'deficiencies'.

 

[OrchidIsa]

I would put the tigrinum in a smaller pot or place some styrofoam pieces in the pot so it dries fast. Tigrinums seem to like a very quick wet / dry cycle.
The niveum, If you have been keeping it less than 18 or 20C it is probably asleep. I would just try to hold it steady until it starts to move before trying to feed it or whatever.

In my office, where the plants are, the substrate is already drying fast so I think that probably the tigrinum is already in that type of cycle...

The temperature never goes less than 18 or 20C and it can go at 26 or 27 when it's sunny outside. When I repoted, the roots were great and there were growing, the leaves as well.

 

[OrchidIsa]

If the roots are OK, then I'd use regular dilute complete fertilizer with intermittent 'seaweed'. That should take care of any 'deficiencies'.

I will try the seaweed. I have some but didn't use it for a while. Thanks!

 

[OrchidIsa]

What are you feeding them, Isabelle?

I use MSU and Plant Prod 25-10-10 at 125 to 150 ppm, alternately, 3 weeks per month. The fourth week is only water. I use my RO water.

 

[Justin]

try mixing back in 50% tapwater instead of the RO. The plants look OK overall.

 

[OrchidIsa]

try mixing back in 50% tapwater instead of the RO. The plants look OK overall.

My tapwater is horribly salty for orchids (and for other things too! )... That's why I installed a RO system. You think that would be a good idea?...

 

[ALToronto]

With RO and PlantProd, you're not giving them any Ca or Mg. And 150 ppm is about 8-10 times too much, especially in an unsuitable environment like an office (way too dry). Get some crushed dolomite for the pots, and cut way down on the ferts. These plants are not using any nitrogen in their compromised state anyways.

 

[Erythrone]

Isa, about 150 ppm: are you talking about nitrogen (N, azote) level or total salts as you measure with you conductivity meter?

 

[OrchidIsa]

Isa, about 150 ppm: are you talking about nitrogen (N, azote) level or total salts as you measure with you conductivity meter?

Total salts with the meter

 

[OrchidIsa]

With RO and PlantProd, you're not giving them any Ca or Mg. And 150 ppm is about 8-10 times too much, especially in an unsuitable environment like an office (way too dry). Get some crushed dolomite for the pots, and cut way down on the ferts. These plants are not using any nitrogen in their compromised state anyways.

Humidity is between 50 and 60%. I use a humidifier in the room.

 

[Paphman910]

You should supplement with Calmag monthly.

Tigrinum does not put out alot of root and it likes to dry out before watering. As we get warmer conditions it like to keep growing so water 2 times a week. Don't give it strong like but Phal light especially during spring and summer during active growth and lots of watering. During fall and winter the medium should dry out before watering and give it brighter light.

The suggestion of a smaller pot is a good idea.

Niveum needs to be looked at esp at the roots. They need an open mix with good drainage.

Good time of year to repot everything!

 

[OrchidIsa]

You should supplement with Calmag monthly.

Tigrinum does not put out alot of root and it likes to dry out before watering. As we get warmer conditions it like to keep growing so water 2 times a week. Don't give it strong like but Phal light especially during spring and summer during active growth and lots of watering. During fall and winter the medium should dry out before watering and give it brighter light.

The suggestion of a smaller pot is a good idea.

Niveum needs to be looked at esp at the roots. They need an open mix with good drainage.

Good time of year to repot everything!

As I said, tigrinum has just been repoted (both actually), it's already in a 2 inches pot. I should put it in a smaller one?? Both have great roots.

The tigrinum is drying between watering... I will give more water as you said, for the warmer months.

 

[consettbay2003]

You are under fertilizing. A total feed of 200-250 ppm would be better. Try for a nitrogen relationship of 50%nitrate/50%ammonium.

 

[John M]

I have not tried MSU; but, I've heard and seen some really bad results. I highly question the quality of some of the batches available out there. I'd stop the MSU. I'd rotate with 25-10-10 and 10-52-10 and a hydroponic feed. For the ones that do not contain Calcium, I'd use Calcium Nitrate at 1/3 the volume of the other fertilzer. So, if you put (for example), a 3/4 teaspoonful of 25-10-10 into a bucket, I'd also add 1/4 teaspoonful of Calcium Nitrate. Don't forget the Epsom salts too. Use at the same (dry), volume as the NPK feed. So, again, if you use 3/4 teaspoon of 25-10-10, then, you add 3/4 teaspoon of Epsom Salts as well. This gets the other two macro-nutrients (Magnesium and sulphur), into the mix as well. Never ever use pure R.O. water on your plants. My experience is that it always causes illness. I wouldn't say to mix it 50-50 with your tap water; but, maybe add 10% tap water back in. Also, when you say your tap water is horribly salty, do you actually mean it has way too much sodium chloride; or do you mean disolved mineral salts in general? If it's the latter, then add 10% back into your R.O. water. If you mean it's actually full of Sodium chloride, then, don't ever use it on your plants.