growers know
STERILIZATION
Sterilizing is more than sanitizing. It is the nuclear option to
discourage pathogens. Sterilization kills all destructive micro-
organisms that may have glommed onto or encroached into
grow media during use. The process doesn’t kill microorgan-
isms going forward, but it does restart the clock. For plant
enthusiasts, there are two basic, reliable sterilization methods:
chemical measures and heat (moist or dry) at levels high
enough to be lethal. When using heat, pasteurization—which is
achieved at lower temperatures than sterilization—may be an
option for some soilless growing applications.
CHEMICAL OPTIONS
“ THAN SANITIZING
MORE
STERILIZING IS
. IT IS
THE NUCLEAR OPTION TO
DISCOURAGE PATHOGENS.”
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grow cycle
Popular chemical media cleaning agents include hydrogen
peroxide, alcohol, quaternary ammonium salts, and bleach.
When using a chemical agent, application and dwell time
are only part of the process. It’s also important to remove any
residue by rinsing again and again—and again. After that,
depending on the type of media involved, thorough drying
might be necessary.
These are some broad guidelines:
BLEACH
10 per cent solution for a minimum of 30 minutes followed
by multiple rinses.
HYDRO CLEANING AGENTS
(CONTAINING QUATERNARY AMMONIUM SALTS)
Effective when used in accordance with the
manufacturer’s instructions.