For some reason, the N-P-K numbers on a fertilizer label are expressed as
weight percent N, P2O5 and K2O, even though none of them really is in the
package as those chemical species.

Gravimetrically, N = 100% N, P2O5 = 44% P, and K2O = 83% K, so a 10-10-10
fertilizer might be looked at as 10 - 4.4 - 8.3.

--

Ray Barkalow First Rays Orchids
http://www.firstrays.com
Secure Online Ordering & Lots of Free Info!


"Wendy" wrote in message
...
Always an interesting topic. I remember reading somewhere that fertilizer
with the
numbers 15-15-15 or 20-20-20 are not balanced?
Why not? Are the numbers not a % of the amount of N, P & K
Cheers Wendy

"Eric Muehlbauer" wrote in message
...
| I always use a high N formula, on bark, coconut husk chips, even
| sphagnum.....with no loss of blooms (although I sometimes switch to a
| high P bloom formula as bloom season approaches). I use Dynagro, Jerry's
| Grow for a few plants (catt's and phrags). Since N is used at a faster
| rate by plants, there is really no need for a balanced formula...you are
| just getting excess P and K wasting away or building up as the N gets
| used up. Although I do sometimes use bloom boosters, I believe that the
| same effect can be achieved by reducing or stopping the fertilizing
| entirely, as I do for some paphs in the winter. Take care, Eric
Muehlbauer
|