Onc. Tsiko Marguerite spike issue
 

My little Oncidium Tisiku Marguerite is throwing me for a loop. It came to me a few months ago in spike, but several leaves dropped in shipment. It had about 8 short spikes on it. One has really taken off, but within the week, 2 turned brown, a few weeks later, 2 others turned brown. I am left with 5 - the one that is doing just dandy, 2 had the tips turn bright green like they were going to take off and one of those is turning darker now, and one of the other dormant seeming ones is turning brown. I have no idea what is going on. It has 2 new growths on it that seem to keep growing. One of the front bulbs 3 weeks ago look like it had a little loop growing that was going to be a new spike, but that has shriveled up. The only thing I can think of is the space heater I added to my work area 3 weeks ago. Maybe it is giving off fumes or something that the plant doesn't like.

It gets watered about once a week - with Dyna Pro orchid food (not the bloomer food) at not full strength every other week, and regular water in between. It gets good light right by the window (south east). I will post pictures soon.

Attached are photos. The medium looks dark because it was just watered today. The mix is the original medium from the greenhouse.

Is the plant near the heater? Does the heater blow on the plant? Is the temp fluctuating a great amount?

It is a good 5 feet from the heater on top of my dresser and it is not blowing directly on it. There is a fan mounted to the wall perpendicular to it that blows lightly by the ceiling to increase air circulation. I don't think the temperature fluctuates widely since the heater has a thermostat that tells it to cut on. I have since moved the space heater even further away in case that is the issue though.

Does the medium look like it needs to be changed out? I usually repot mine, but since it was in spike, I have avoided doing it.

I find buying plants in spike or bud is always an iffy proposition. The change in environment can cause bud drop or blasting. I would repot it into fresh mix, if any of the spikes bloom that's great. If not, you'll be ready for nice blooms next year.

Bill

I agree with what Bill pointed out.
Spikes and buds can be quite sensitive.

When they are brought home, blasting is not uncommon. Much drier air in the home is often the major cause for sudden death of spikes and buds.

Orchids at nursery are grown at nearly perfect condition.

Your plant will adjust to its new environment and flower fine next time.

Oh I agree and believe this to be true. I just think it is odd that the plant seemed stable after loosing the first few spikes the first week it got here, and now several weeks later it is now loosing 2 more spikes. I think the first round I lost was due to exactly what you describe. Now, however, I think it has been here long enough that it could be something I am doing (or not doing).

It could be something in the air then. fruits nearby?
any gas fumes or new paint??

The only thing I can think of would be the space heater - in case something on the heating coils is giving off fumes. Could this be the culprit? Do I need to just not use it, or is it ok that I moved it further away (around 6 feet away and blowing in the opposite direction now)

well, if there's fume in the living space, it's likely that it is present everywhere for the plant to be affected.
I wouldn't stop using heater just for a plant, especially when you're not sure that's the cause for the drying spikes. but it's your call. ;)