IMHO, both water and fertilizer need to be reduced in winter for almost all
orchids. "Winter" of course varies by location, and sometimes yearly even
at the same location, and the degree of reduction varies by the type of
plant. Some need a serious fast, others just to "cut back."
On the formulation of fertilizer, there is tons of conflicting research
floating around, esp. on whether urea nitrogen is useful for orchids. I
have not studied hard enough to come to a firm opinion on that one, but tend
to lean toward the "non-urea is better" school of thought. [Although I can
see that this might also be dependent in part on the potting mix.] On the
"numbers," e.g., high nitrogen (30-10-10) vs. a more balanced formula, there
appears to be a pretty good concensus that you need the former if growing
mostly in bark, and the latter if growing mostly in other media.
The few things I am willing to stick my neck out on:
1. There is NO perfect fertilizer for ALL orchids in ALL situations.
2. It is FAR better to underfeed than to overfeed.
3. Weaker, more frequent applications, are better than less frequent,
stronger feedings.
For us, in our conditions and our potting mixes, we like the Dyna-Grow
"Grow" formula, but we still have to add extra magnesium in the hottest
months of summer.
Good growing,
--
Kenni Judd
Juno Beach Orchids
"Lady Blacksword" wrote in message
...
If you see a lot of change during the winter from a fertilizer, it's not
always a good thing. Your plants should be resting or blooming this time
of year, not growing. So the fertilizer should not be forcing them to
grow.
If anyone more experienced than myself dissagrees, please jump in.
Murri
"Jack" wrote in message
oups.com...
The explaination that I got was that is that urea breaks down slower in
soil, but potting medium in most orchid culture is aseptic (clean or
inorganic) medium than lacks the microbes to break down the urea, which
is why I was told to buy urea free fertilizer, as the urea still forms
salts that affect the plant.
Also, how do you like SuperThrive, I bought some the other month and
have been using it since then (9weeks) I din't loose any plants to
transplant shock, but haven't seen any "Super" results other than that.
Jack