Leo A. Martin leo@possi.org
Tue, 16 Apr 2013 23:15:12 PDT
For seedlings I generally use a FoggIt nozzle on a hose. I have also learned how to hold
one cupped hand, palm-up, almost on the surface of a seedling container, and pour liquid
into my hand to wet the container without disturbing the soil. Then sometimes I use a 1
liter squeeze-pump spray bottle, the kind that may hold water for ironing clothing.

I have a Chemilizer fertilizer injector plumbed into my outdoor drip system for my
garden and many of my hose bibs. It is not cheap but it is an immensely useful tool. It
is on a bypass loop so I can use it or not when I irrigate. This is a unit plumbed into
a water line which has a sidearm nipple connected to a length of tubing that goes into a
barrel containing concentrated fertilizer (or acid, or whatever) solution. When water
runs through the injector the water pressure sucks fertilizer concentrate into the
outflow limb of the circuit and delivers it to the drip system. This would not be
considered portable unless one attached it to a rolling cart and had a means to connect
and disconnect from one's watering system. It makes a huge difference here to give
garden plants not only dilute nitrogen with every watering, but also acid for plants
like cycads that tolerate our alkaline soil/water but grow much better with lower pH.
One can also fill a bucket with fertilizer water from a hose bib plumbed into the system
and take the bucket into the house for the house plants.

Chemilizer makes their units for commercial chemical production. The materials are
designed to withstand concentrated corrosive chemicals. Several years ago when an
engineer here in metro Phoenix who gardens for a hobby bought one from the company they
were surprised to find their device is of interest to gardeners.

They make two models. One is fully adjustable as to flow rate and thus dilution of the
concentrate. The other delivers a fixed dilution via a plug-in proportioner. These are
available for many different dilutions and so one may buy a unit that delivers any
concentration desired. The delivered concentration can be changed by changing the
proportioner, which is a little bigger than a large pen. But of course one can also
change the final concentration delivered by varying the concentration in the concentrate
reservoir, so either Chemilizer unit can deliver variable concentrations if the owner
does a little math.

I bought the fixed dilution model because is is much less expensive. To use the device
one must first add ammonium sulfate to the desired concentration in a batch of water,
then do an acid titration on the nitrogenated water to find out how much vinegar (or
other acid) to add to change the the desired pH. Then one must add the proper amount of
acid to the concentrate. There are standard tables one may look up to figure out how
much ammonium sulfate or the like to add to the concentrate to deliver a desired amount
of nitrogen in the irrigation water.

The company appears to have been acquired by another company, but their Web site is now


There are other companies making similar things. I have been told there is a company in
France but I don't recall the name.

Leo Martin
Phoenix Arizona USA

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