There is a wealth of information available at this website:
Orchid, Water Quality, Fertilizer, pH Management, Nutrition
Specifically, there is good information on selecting a good fertilizer for your water supply and plant needs at this link, which can also be found at the previous link:
http://www.staugorchidsociety.org/PD...ySueBottom.pdf
If you go down to page 7 of that second link,
Table 4, there are many fertilizers listed, their characteristics and formulations. You can also find some very general fertilizers guidelines at the top of the same page. You can mail order if you want to, but you can also find fertilizers locally that should meet your needs for Cattleyas.
Table 5 give general proportions of plant nutrients that you should provide. There used to be a concern that nitrogen provided as urea was not being properly used by the plant - that has been disproven be recent scientific research, so I usually don't worry about that. Look through that document and understand what the included tables are telling you.
If you read all of the stuff at both of those links - your head is probably swimming and you are close to just getting some "purty plastic plants" instead.
So, here is the "Tweet" version:
Fertilizer should provide N-P-K, equal numbers or P number lower. Provide Ca and Mg if not already in fertilizer. Provide less fertilizer rather than more. (If you are an older person like me, we used to call this the "Reader's Digest" version.)
One of the best Cattleya hobbyists I know once told me that he never fertilizes his plants. Then, he modified that and said "almost never - maybe once or twice a year". I don't go quite that far, but I find Cattleyas and my other plants do better if I fertilize them weakly and not too often.
Fertilizer for Cattleyas
Linear Mode
