Maximum Yield Australia/New Zealand January/February 2020 | Page 40
“HYDROGEN PEROXIDE
can be used in a hydro system to
increase the sanitation level and
will not harm the plants.”
FLUSHING WITH OR WITHOUT PLANTS
If you notice plants in your hydro system are starting to
look sickly or show signs of stress, you may be tempted to
try and flush your system while your plants are still in it.
Your plant leaves may be curling, getting brown spots, or
if you accidentally add too much of a particular nutrient or
are noticing some algae in your water — but your plants
still look otherwise unaffected — it may be time to do an
unscheduled flush. This can be done while your plants are
still growing in the system if done carefully. Do not try to use
any flushing agents not approved for use with plants if you
are leaving your plants in place during a flush. The plants
will absorb the chemicals and at best will kill them. Worst
case, it won’t kill them, but the plants will have absorbed
the chemicals and the end consumer will end up eating
them. If flushing with plants in your hydro system is the best
course of action, there are a couple of options.
Hydrogen peroxide can be used in a hydro system
to increase the sanitation level and will not harm the
plants. Hydrogen peroxide will help the plant by providing
additional oxygen to the roots. This is true so long as
the amount used is not excessive. Start with food-grade
hydrogen peroxide which is usually in a 35 per cent
concentration. Dilute this with 10 to 12 parts deionised, RO,
or distilled water to reduce the concentration to about three
per cent hydrogen peroxide. Add one to two teaspoons (five
to 10 millilitres) of the diluted solution per each gallon (four
litres) of water in your system. Adding vinegar is another
possibility, but this can be tricky if care is not exercised.
Vinegar will lower your pH, so keep that in mind, but it won’t
harm your plants if diluted enough. Dilute white vinegar
down to a similar ratio of the hydrogen peroxide of one to
two teaspoons (five to 10 millilitres) per four litres of water.
Be prepared to adjust the pH accordingly, though.
FLUSHING SALT AND NUTRIENTS FROM SOIL
Flushing is sometimes a necessary step in soil culture
too. If salts have built up or the plant has received
an overdose of nutrients, it can often be saved with a
flushing of clean water if caught and acted upon in
time. A volume of water at least three times the volume
of the container is recommended to try and leach out
the unwanted nutrients or other foreign substances.
Plants grown in soil culture that do not get flushed
when salts build up are prone to root rot or other
diseases that will kill the plant or affect the yields.
Some growers flush their soil-grown crops as a matter
of course during the last couple weeks of the plant’s bloom
so that it will be sure to use up all its stored nutrients.
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Maximum Yield