get the same nutrients as if it were eating a plant with no silicon. This significantly increases the amount of time the insect
needs to develop and allows for other control tactics such as
biological control to provide pest suppression. This slowdown
in individual growth can also slow down population growth
and may allow for the crop to outgrow the pest. It may also
force the pest to undergo more mouth-part wear as discussed
earlier. This theory is only applicable in a few plants that accumulate very high levels of silicon, such as cattail or equisetum.
The last theory relates to how silicon may chemically react with
ions in the water, making them unavailable to plants. This has
been shown in soils with high aluminum concentrations. When
silicon is added to the soil, the aluminum and silicon bind
together and fall out of the solution, making the aluminum
inactive. This is also thought to work positively to alleviate some
salt toxicity issues, which brings me to my last point. Because
silicon interacts with some ions at high concentrations, it can
cause precipitates in nutrient solutions if used too frequently.
Be sure to test any silicon product on a small scale first before
adding it to your system, and follow the manufacturer’s
directions on the label. Silicon will also interact with itself at
high concentrations in a neutral pH. This is why most silicon
products are formulated at a high pH. Silicon is easily buffered
in solution, and at low concentrations it will have little effect
on your pH levels, but this doesn’t mean you should abandon
monitoring your pH levels going forward.
All of the research suggests silicon is a beneficial element when
it comes to plants, especially in hydroponic systems. Plants
evolved growing in soil containing silicon, so it only makes
sense they will continue to need silicon when they are grown in
water culture.
“When silicon is added to the soil,
the aluminum and silicon bind
together and fall out of the solution,
making the aluminum inactive.”
Maximum Yield USA | April 2015
143