Tall micranthum seedlings

[dan_t]

Hi everyone

Sorry I haven't been around for a while - just had over 3000 posts to read through - seems I missed a lot!

Anyway, to the question. Almost exactly 6 months ago I deflasked a flask of micranthum. They're growing really nicely, except they're going upwards!! They're now about 2 inches tall, with well spaced leaves. All the other flasks I deflasked about that time are looking much more normal.

I'm coming to a point when I want to re-pot to keep them growing strongly, and was wondering what I could do about their growth habit, if anything? Should I pot them a bit down into the medium, or just let them be?

Thanks

Dan

 

[NYEric]

Photo?

 

[Kyle]

More light.

In my experience, armeniacum and micranthum will have long internodes if they are grown in low light.

Potting them deeper in the media will help, but only if you solve the light problem.

Kyle

 

[SlipperKing]

I agree with Kyle

 

[Roth]

First reason can be the light, but there are two others I found out the hard way...

- pH of the potting mix too low...
- Too much water, even if the roots look nice...

 

[dan_t]

Thanks for the replies - I will post a photo when I get home tonight. For light, they are about a foot away from a 40W daylight tube, which I thought should be enough - am I wrong here?
Water - I tend to underwater if anything so I doubt that's the problem. Potting mix - they're in bark/perlite/charcoal mix I use for all my paph seedlings.

I have malipoense growing really nicely in the same conditions, as well as Ho Chi Minh - both have normal compact growth and were deflasked the same time.


Will post a piccy soon

Dan

 

[Kyle]

That is not enough light. From my observation, growing about around a dozen of each, they require more light then the rest of the parvis or mottled leaved species. Think multifloral. The light from one 40W flourescent is not very much. You might get away with a T5 flourescent.

Kyle

 

[Ernie]

For light, they are about a foot away from a 40W daylight tube, which I thought should be enough - am I wrong here?

Dan

Yeah, I think this is your problem too. I'd use at least two 40 w tubes for seedlings (three or four is better once they're adapted to being out of flask), AND get them closer to the tubes. Close enough that they don't touch, and room to water etc. I love it when I can get them 6 inches or less from the tubes. Although it is geared toward adult plants, you might want to look at my article in Orchids, Dec 2007 (below). Better yet, invite me to give the live version to your local orchid society.

http://enlightenedorchids.com/The EnLightened Way Orchids December 2007 v76n12.pdf

-Ernie

 

[dan_t]

Thanks all of you - I'll put in the photo anyway, but I'll try to increase the lighting in there to compensate.

Are these like malipoense in the way they will put out roots further up the stem if I plant them into the medium a little, or do I just wait until the next growth starts?

Dan

 

[Kyle]

They will usually start at least one root at each internode. So, bury the nodes and they will develop roots.

Kyle

 

[Roth]

Thanks all of you - I'll put in the photo anyway, but I'll try to increase the lighting in there to compensate.

Are these like malipoense in the way they will put out roots further up the stem if I plant them into the medium a little, or do I just wait until the next growth starts?

Dan

You can pot them a bit deeper, in a coarser media with lime. When I was growing and blooming micranthum under fluorescent tubes, I was using 2 tubes TLD 36w/33 for 150cmx50cm area, about 30 cm from the plants. At that time I noticed that mottled leafed parvis grew like crazy and with very compact growth with 10-52-10 fertilizer 0.5g/L as their main dish, sometimes a bit of calcium nitrate and magnesium sulfate. I had a couple dozen plants, should try to find out the pictures somewhere if it is not in the laptop that has been stolen... They would mature an excellent growth in 1 to 2 years. Whenever I applied a 28-14-14 or similar, they would not look as nice.

The more I am growing paphs, the more I think that sometimes we give them usually too much light, and we try to feed them more only to compensate for that extra light...

 

[etex]

Ernie- That is one awesome article you wrote!!

 

[wonderlen3000]

Actually it's perfectly normal. I have urbanianum seedling, deflasked about 6 months ago and are pretty tall, just like yours. I think almost all the seedling I had seen so far, are pretty much like that. The growth will become less tall as it get closer to mature.

Only bad thing is the roots will come out at the internode, so you have to keep a very moist potting mix or just cover the pot with 'clear plastic' cup and it will keep the humidity high.

 

[paphioland]

The more I am growing paphs, the more I think that sometimes we give them usually too much light, and we try to feed them more only to compensate for that extra light...

I would strongly agree with this. Longer, lower levels of light that is my paph leaning in recent years.

 

[Leo Schordje]

I'm inclined to agree with the guys suggesting more light. With cordial respect to the two suggesting less light, you are growing under lights, rather than in a greenhouse.

As to what to do, when you repot, I would remove lower leaves until you find a root node at the leaf base that has not turned brown & hard. BUT leave at least three leaves at the top, regardless of the color of the root buds. Then bury the exposed stem and root buds. It is important to get active roots into the mix, without roots you can't get much in the way of vegetation.

 

[Ernie]

I'm sticking to my guns too. Could certianly be a nutrient issue instead/too though. SO, ***under our nutrient regime, stretching is from low light in our experience.***

Also, I've learned to decline flasks where the plants have gotten leggy like this. Becomes a rescue project most times.

-Ernie

 

[Bolero]

I've had this problem before, in fact I have plants like that who have longs stems on them. The light issue seems to correct it, it takes time and it doesn't really impact on the plant.

Burying it deeper is certainly the solution.

 

[Roth]

Also, I've learned to decline flasks where the plants have gotten leggy like this. Becomes a rescue project most times.

-Ernie

I do the same indeed, always problems. Pot some leaves below the mix, with the risk of rotting the seedlings, OR pot them up, with the new roots drying up ? Mess or... mess...

Sometimes in the flask people put too much nitrogen and hormons, makes for extra leggy seedlings. Now when I buy flasks- I am careful with the ones I do, I reject too the seedlings that do not have at least the 3-4 latest leaves at the same level...