Repotting, Oncidium, bark or bark and sphag
(need a heavy decorative pot to put it in). Several blooms broke (never expected them to be brittle). I don't think it will be too long before I am ready to cut the spike and repot. I can't really see what's in the pot it's in now, but the top looks mossy. This is in an apt, so the AC will keep the environment pretty dry. I've read that these like to stay a little moist (I guess like a Phal?) unlike my Catt that would prefer to go dry before watering. If that's the case, should I use a mix of bark and sphag to help hold in more water? 
Reply With QuoteOncidiums have thin roots which don't like to be too dry, so you'll want to go with small size bark. Plants with thinner roots usually prefer smaller bark, and plants with thick roots like a coarser mix. If overwatering is a concern for you, you could use a mixture small and medium bark. I don't like to use sphag at all, but if you tend to underwater your plants, adding a little bit would help keep the roots from getting too dry. I see a lot of Oncidiums being grown in pure shpagnum, but that isn't for me. I grow my Oncidiums in a mix of fine bark, sponge rock, and charcoal. I'm more likely to overwater than to underwater, so this is a good mix for me because it is fast drying, but still holds moisture. The roots seem to enjoy it.
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Originally Posted by notsogreenthumb
