The fact that the bulk density can vary between
formulas further complicates matters.
Another problem is that many of the raw ma-
terials are extremely hygroscopic, meaning they
“suck”
moisture
right out
There are some issues
of the air
with fertilizer powders that
over time.
can complicate life for the
As there is
no practi-
hobbyist. One of those
cal way for
problems may be a lack of
us to know
homogeneity
exactly how
much water
has been ab-
sorbed, we can no longer use weight to accurately
measure how much to use, and as it affects the
bulk density as well, volume measurements are
thrown off as well. So what can we do?
The answer is really quite simple: make a con-
centrated solution! Please Note: This is an example
only; you may wish to make a more concentrated
solution for convenience, but keep in mind that
two pounds per gallon is a practical upper limit
to the solubility of most fertilizers. I recommend
staying closer to one pound per gallon for stability
of the solution, especially for formulas containing
calcium.
Before you even open the powder container,
read the label to determine the net weight.
Remembering that a pint of water is a pound in
weight, pour fi ve pints (two quarts plus a pint) of
hot water into a sealable container for every pound
of fertilizer powder in the package (if you are deal-
ing with metric measurements that would be fi ve
liters per kilogram of powder.) Add the powder
and stir or shake to completely dissolve it.
You now have a 1/6th -strength (16.67%) con-
centrated solution of your original formula. In
other words, if the original powder was 18-6-12,
your solution is one-sixth of that, or 3-1-2.
The advantage of this is that it’s totally uniform
(just be sure to shake well before measuring it).
It’s not going to absorb more water from the air
(keep the container closed to prevent evaporation),
and you can now work on a volume-to-volume
basis to mix your nutrient solution. GG
Ray Barkalow has been growing orchids for over 45
years, and owns First Rays, which offers horticultural
products to the hobby grower. He may be contacted at
raybark@fi rstrays.com and you can visit his website at
FirstRays.com.
March 2019
THE ORIGINAL TWO-PART,
PH BALANCED HYDROPONIC
BASE NUTRIENT.
•
•
•
•
Ensures maximum growth and flowering
Highly concentrated
pH balanced for increased yields
Over 20 years of outstanding results
High Performance Products.
High Performance Service.
To see the full line of products and find
a dealer near you please visit:
www.tradewindsgarden.com
www.GardenandGreenhouse.net
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