oncidium in wrong medium, in bloom

[Stray59]

aleksanne brings up a interesting point about a decision we all have to make when we buy an orchid in bloom; repot or leave it alone. It is true that often (although not always) you will lose the blooms if repotted when in spike; and it is also true that if you don't repot into a medium that is friendly to your environment you stand a chance of losing the plant.
So what to do? I make this decision based on several criteria - here are the main points I consider:
- How much did the orchid cost? - How easy can it be replaced if I lose it? - How much do I like the plant overall? - Which would I rather have - a plant which remains in my collection for years, or just long enough to give a shot of color to my home ( I have bought cheap Phalaenopsis in bloom just like cut flowers - I knew the plant was not happy, but I wanted the blooms and the plant was cheaper than buying a flower arrangement).
We all like to keep blooms when we can, but in my opinion, I would rather have a healthy, thriving plant for years and I will sacrifice this blooming cycle if I know the medium is going to cause me trouble.
This also goes for choosing the plant to purchase. If there are several plants of the same variety, some in bloom some not, I look ONLY at the health of the plant and purchase the best one, regardless of bloom spikes. Of course, I can do this easier as I have a large collection and always have something in bloom or moving into bloom; this lesson has been something I learned over time. We all like to bring home a plant that you can show off, but for the serious collector, you have to purchase the BEST PLANT to add to your collection - the blooms will come.
Hope this helps some make better decisions than I have in the past. I have lost a lot of orc's because I have chosen to keep the bloom spike rather than repot the plant right away, or I purchased a plant because it was in bloom rather than choosing the healthiest plant.
Lessons learned!
Steve

[aleksanne]

Originally Posted by james mickelso

Wrong media??? [paragraph cont.]

This is my first oncidium so Im rather clueless. I did a bit of research and every resource I have found claims loose and airy media is appropriate (vs. the soil-like mush my onc. is currently growing in). I picked it up at an orchid specialty store in NYC, so Id assume they know what they are doing, but the conflicting info I found online made me worried.

At least we agree that the media is 'wrong' for my growing conditions.

Im new to this; I know I do not have greenhouse conditions but I try to care for my 'chids in the best way I can. The room they are kept in is always between 74-77* F and I have a humidifier on almost 24/7 to keep it at 55% humidity. Sunlight comes direct from a NNW windowsill. Id like to think my orchids arent suffering, but I may be wrong...

Your onc. is beautiful, by the way

[NYCorchidman]

Hi, there!

Ok, after seeing the picture, I can better help.
ALL my oncidiums and miltoniopsis came in the same mix you mentioned and it is not soil. It does look and feel like soil though!
It doesn't drain crazy well like say, bark chips, but it retains moisture well, which works great for oncidiums.

The only thing is to watch for watering and make sure the mix doesn't stay too wet.

If you disturb the roots in that mix now, you will lose the flowers and the plant will be set back.
You will see why when you check the root mass in the pot later for repotting.

For now, just water your plant carefully and enjoy the flowers.
Even when you consider repotting it, I would not recommend repotting into something too open. Unless you plant to stick this plant into an orchidarium or greenhouse with humidifying system.

Oncidiums need lots of water while growing.
Another point is moving oncidiums from moist mix to dry mix like straight bark tend to dry and stress the plants unless you are very good with watering and humidity.

[mattryan]

I agree with you orchidman. Except I have all my onc's in a bark perlite mix and they do great, but I have a min. of 50% humidity in my house. I think you have to also think how much you water. If you water too much, too often maybe a more airy mix would be much better. I would think especially if it's your first onc. or until you find out what would suit your conditions best. Just a thought
cheryl

[Stray59]

NYCorchidman and mattryan's comments just go to show that the medium you choose will be dependent on your growing environment. Your humidity, watering schedule and air flow will all determine which medium is best for you. Sometime you just have to try and try again to find what works for you.
Good luck with the Onc. - may you have a bounty of spikes and growth!
Steve

[james mickelso]

These are great comments. My answer was somewhat tongue in cheek. but the gist of what I wrote pertains to what I have experienced. A little history may help. When I started growing different orchids I was amazed at what I thought I knew about growing and what I didn't. Oncidium Gower Ramsey and Brassia Rex along with the Wilsonaras. I love them. But the first ones I tried to grow all died. Why? Root rot. Plain and simple. I had heard the refrain about "oncidiums need water. Lots of water". I found out different and after some experimentation hit upon the truth of different medias and how orchids react to them. Oncidiums don't need high humidity. What they need is constant moisture at the roots. That is different from lots of water. The brassidium you see in the picture is growing in a very coarse bark/sponge rock/charcol mix. The plants are watered heavily, and then they dry. With an average of around 40-60 percent humidity all the time, they grow very well. But they are not watered all the time and kept anything near wet. They are watered when they have dried completely. The pot is weighed (just by lifting it) when wet after watering, then allowed to dry to the point where the pot becomes very light. Then it is watered heavily again. For my environment that is about once a week in summer. In winter that is once every 14 days or so. And lately with the cold it is about every 20 days. They are doing very well. Somewhere like say Chicago or New York where the humidity is much more variable, I might opt for some chopped up spagnum moss in the mix. Not to keep the root mass "wet" but to keep the root mass moist. There is a big difference. Oncidium alliance orchids are very suseptable to root rot. So the best way to keep them healthy is to make sure the root mass has sufficient moisture but also has good aeration in the media. Oncidiums have a dense fine root mass and although the surface media and even the outside volume in the pot dries, the interior can be too wet and harbor rot producing fungus and bacteria. That is why I opt for a corser mix and then I can water more often without the bane of root rot. Those who grow onc's well have found the media that work for them in their environment. I just think that the two most important considerations in growing onc's well are sufficient moisture at the roots (but not wet) along with adequate air movement around the plant. And when repotting, it is imperative to wait until the new growth has started putting out roots. Like the pictures show, and I have many more if anyone is interested, this will be when the new growth is at least halfway to maturity. Your mileage will vary but this is a snapshot on how oncidiums and their relatives grow well.

[NYCorchidman]

Originally Posted by mattryan

I agree with you orchidman. Except I have all my onc's in a bark perlite mix and they do great, but I have a min. of 50% humidity in my house. I think you have to also think how much you water. If you water too much, too often maybe a more airy mix would be much better. I would think especially if it's your first onc. or until you find out what would suit your conditions best. Just a thought
cheryl

Agree.
I personally believe open mix with good watering and high humidity is the ideal way to go, which is hard to achieve at home growing condition.

My oncidiums are all sitting by bright window, the only place I can provide for them, and in the summer time, they suffer a lot. I try my best but I just can't keep up with correct watering. I go away or I forget and so on.

However, when I am staying in a lot and able to water them good and mist the exposed roots like crazy everyday, they show amazing growth.

By the way, I do grow mine in rather open mix, but some are in moist mix and they do great because of my poor watering in the summer.

[james mickelso]

I do the same when I am too busy and the orchids do fine. Sometimes I work too much and the orchids even in summer don't get watered as much as they should. But I have lost more orchids to waterlogged media than all other causes combined by a long shot. I have never lost an orchid to underwatering. never. Not even phals. I just watered my orchids this morning after nearly three weeks without any because of the cold. I couldn't water in the morning because it wouldn't warm up enough until early afternoon and it was too cold when I got home in the evening. So I just left them alone til this morning. I just hosed them down (he cringes). They are all fine. No deterioration at all.

[NYCorchidman]

overwater-root rot-quick death!

underwater- much slower death. hahaha

I forgot to water some plant including little tolumnias. Some dried up and died. some looked dead but came back to life after good watering. It took a loooong time for them to recover.

Ok, now we are taking this thread astray.

[aleksanne]

I think Im learning more from the astray topics, :P

Thanks again everyone; I learned a lot from you guys & gals!