I am of the belief that 1) orchid nutrient demand has nothing to do with
the medium, and 2) the formula is not necessarily all that critical as long
as you provide the right balance of nutrients - including macros, micros and
trace elements - and provide enough, but not too much. Controlling the pH
is possibly more important.

Back before folks understood orchid culture as well as we (claim to) do
today, it was typical to go several years between repotting. In that time,
the microorganisms that break down the bark also consumed a great deal of
nitrogen, hence the high-N fertilizer formulas. With the various media used
today, coupled with the more-frequent repotting to avoid decomposition, that
is far less of an issue, if it is one at all.

If you are lucky enough to have a really good supply of osmunda fiber, its
decomposition will release lots of nitrogen, so maybe one should adjust in
that case.

--

Ray Barkalow - First Rays Orchids - www.firstrays.com
Plants, Supplies, Artwork, Books and Lots of Free Info!


"Diana Kulaga" wrote in message
...
I started out using Peters 20-20-20 with micronutrients, and then switched
to Dyna Gro. Haven't tried the MSU formula, but lots of people here love
it. Since Dyna Gro is generally not available unless I either go somewhat
far afield or order it (shipping costs add up that way), I recently went
back to Peters. After several years of using DynaGro I just didn't see a
difference in plant performance. Mind, that is anecdotal, based on my
experience only.

Diana