Oncidium killer

[alvin2000]

I've got some orchids from different genera and most of them are doing good in my care, except oncidium.

I've already killed two oncidiums( dancing lady and a noid)and now the sharry baby is on the line for its demise while the other two are running slowly to orchid heaven.

I've tried s/h, but no growth for two months and the psuedobulb is wrinkling fast.( there are new root growth before converting to s/h) I checked on the roots but it seems ok and not rotten, so I thought they don't like s/h.

I transferred them to regular pot culture using LECA and watered every 2 days when the LECA is close to dryness but nothing is happening for almost two months.

Am I doing the right thing fro my oncidiums? I really don't want to give up on this. I hope somebody could help me.

I grow them outside with bright indirect light.

[kraai]

Mine seems to be happy, she is planted in bark & I follow the following advice I got from a web page:

Culture: Oncidium Sharry Baby 'Sweet Fragrance' needs a well drained compost and full to partial sun. In the greenhouse, we use compost consisting of Osmunda or tree fern fiber, with sphagnum moss and small bark chips added to ensure good drainage. The plants are watered and allowed to dry before adding water again. We fertilize the plants weekly with an orchid special fertilizer during the growing season. Plants do best with morning sun and afternoon shade. In the greenhouse, we started growing them in full sun and the leaves tended to produce brownish spots. After moving the plants to a new shaded location this stopped. The plants should never be subjected to temperatures lower than 60°F (15°C) at night. During the winter months, water is restricted to watering plants only enough to keep the pseudobulbs from shriveling.

[delphiguy]

I have killed a lot of oncids... anyways... I've always find that S/H is a hit and miss... the
plants would do well for a while then after a few months they decline almost instantly.
Then I learned that maybe there's some baddies in the water with the S/H, so i washed the
media every now and then (every 3months or so) and now they're happy as can be.
Anyways my Sharry Baby is doing fantastic in S/H (its a backbulb rescue). My phals I've
taken out of S/H and grow them mounted instead. I abandoned S/H for Bulbos as well.

I'd say if you can get a backbulb from those oncids go get one before its too late and
put it in a container and bag it until it produces new leads. If S/H is not working for you
then grow them conventionally like you do now.... btw, what size LECA are you using?
there are the smaller ones and the bigger ones, i always use the bigger ones as that
allows for more air to the roots. Good Luck.

[alvin2000]

Hi Randy and Maria,

Thank you for your suggestions.
Randy, I use a medium size LECA, almost a size of a thumb nail., or a bit smaller since oncidiums is fine rooted plants. I clean the LECA very well before using it. I soak it for 3 days with regular washing everyday and bring it to boil before using. I have some Phals in s/h and they are like ducks to water. I really don't know if putting them in a plain LECA is a good idea, but I have to try it this way.

I put it on a clay pot so I can water them daily but until now the pseudobulb is shriveling to death.

The plants receives morning sun until 10:30 and filtered sun the rest of the day.. Am I doing the right things when it comes to watering and light? Are these dancing ladies ,Sharry baby and twinkle needs dryness before watering?

[smwboxer]

Every two days is way to much watering for your plants. They need to dry out well between watering.

[alvin2000]

Every two days is way to much watering for your plants. They need to dry out well between watering.

I grow them in a 4.5 inch clay pot and I think it dries faster. Do you mean total dryness of the LECA before watering again?

[Brutal_Dreamer]

... Do you mean total dryness of the LECA before watering again?

IMO - Yes. Oncidiums have pseudobulbs to retain water so their roots need to dry out before being watered again. Leaving them constantly wet will cause root loss and the leaves will turn yellow and fall off of the p-bulbs. The p-bulbs will also start to shrivel because they do not have roots to pull in the water that they do need.

Cheers,
BD

[Raver]

its probably too much water, i have a few oncidiums in s/h and they were doing the samething yours were but now they are doing fine and growing alot of new roots. Just dong water they too much. I spray the roots every couple of days so they wont dry out.

[alvin2000]

Thanks BD...Now I should water them about 2 to 3 days or when the LECA is completely dry.

[alvin2000]

its probably too much water, i have a few oncidiums in s/h and they were doing the samething yours were but now they are doing fine and growing alot of new roots. Just dong water they too much. I spray the roots every couple of days so they wont dry out.

Thanks Raver for the tips...