Fertilizing Oncidiums
 

I know that 20-20-20 seems to be the general advice for fertilizer, however, the AOS Oncidium sheets recommend 30-10-10 for Oncidiums in bark. Just wanted to know if this works well?

=(

Unfortunately, those AOS sheets, while OK for basic info, are quite outdated, and don't take into account different individuals' environments very well. Personally, I recommend against such high-nitrogen fertilizers, as they can retard-, if not stop blooming altogether if overused.

There are microorganisms that live in bark and slowly consume/degrade it. As they do, they consume nitrogen, so the fertilizer formula was adjusted with extra nitrogen to compensate.

However, the population is very small in fresh bark, so that is not a factor, and with up-to-date culture, we tend to repot sooner as the bark decomposes - when that critter population is at its max - correcting the issue once again.

Hi, I am new, and I don't know how much you know about orchids, so if I tell you something you already know, please excuse me. I am just being thorough. :)
They reccommend that because the bacteria that break down the bark use up a lot of nitrogen. For me, I use any of the orchid fertilizers so long as they don't have nitrogen derived from urea. Urea N takes a while to break down, so it doesn't get used by the orchids because it rinses out of the medium when you water. So, make sure to use a special orchid fertilizer-I use gubler personally. I also have schultz and wonderlizer, but they both have urea nitrogen, so I stopped using them for my orchids. I didn't know this bit of info about the urea until recently. Use a high nitrogen fertilizer, usually 1/4 strength every week, or every second or third watering. I don't know if you have heard the expression, "weakly, weekly" but it is a good rule to follow. Then, about a month or two before it is time for my orchids to bloom, I start using a high P and K fertilizer. It has a low number at the start, and then a high either middle or last number. Can't remember which. Lately, I have been using "spoonit bloomit" fert. from fred myer. It is 6-30-30. I can't say if it works great yet, but it hasn't hurt my plants, so that is always good. I decided to try something new, because I ran out of my schultz flowering fertilizer.

Also, I have heard amazing things about a product called worm tea. I bought some worm poop to make my own, but I don't know if it will work as well as the stuff I have seen online. If you want to know more, there is info about it on orchidgeeks.com in some of the threads. You can do a search for it on there, and it should be easy to find. Anyway, I am sure there are people here who know way more than I do about fertilizers, so just take what I say with a grain of salt.

Thanks guys =) I am researching worm tea right now.