Silicon: The Misunderstood Element
What is silicon?
Silicon is perhaps more misunderstood and under-appreciated than any other element. Widely viewed originally as an element not essential for plant life, now silicon is scientifically known to provide countless benefits to plants, benefits that cannot and should not be denied. Because of its highly particular nature (i.e. high pH and tendency to precipitate/fallout in solution if mixed incorrectly, etc.) and widely misunderstood necessity, it is commonly omitted from hydroponic nutrients. However, just because it is not included in most nutrient brands product range, does not mean that it should be excluded from your garden or deprived from your plants.
The primary issue with attempting to classify silicon’s essentiality to plant life stems from silicon’s abundance on our planet. It seems that silicon can be found just about anywhere (and rightfully so, given that roughly 28% of Earth is comprised of silicon). What we do know, as a result of numerous silicon-additive studies, is that plants fare much better throughout all growth cycles with the addition of silicon through increased yields, growth and protection against toxic heavy metals, cold and heat stress, pests and pathogens (fungi and mold).
By mass, silicon is the eighth most common element in the universe and is also the second most abundant element on Earth. It is interesting to note that nearly 90% of the Earth’s crust is composed of silicate minerals (containing oxygen, silicon, and various reactive metals - Mica and Feldspar are great examples). These complex silicate minerals are the most commonly encountered form of silicon. Very rarely are pure, elemental silicon crystals ever found in nature. It was initially believed that silicon was transported along with water, but recent research has indicated otherwise. What we now know is that silicon is actively absorbed through various transport proteins, as shown by the recent discovery of silicon transport genes in rice species (Ma et al. (2006)). The specific transporters are Lsi1 and Lsi2 (Lsi = Low-silicon) and are located on the distal and proximal sides of the endo and exo dermises of root cells, respectively. From here, movement continues upwards as an inorganic solute into the xylem, much like other elements (e.g. potassium).
What are the benefits of silicon?
While silicon provides many benefits for plants including increased shoot and root density and increased yields (of which up to 65ppm of Si has been shown to be the most advantageous in hydroponic systems), it more importantly provides a much needed defense for plants against both biotic and abiotic stressors. Silicon is unique in that it provides both physical and biochemical protection. It is widely known that silicon is deposited in the cell wall of many plants, however, research has shown that silicon deposits are also found in trichomes. These deposits act quite literally as a physical barrier, preventing attacks from pathogens and herbivores. Given that trichomes are the primary site of secondary metabolite production, bolstering trichomes results in a more efficacious use of a plant’s endogenous secondary metabolites for pathogenic protection and an overall increase in trichome quality and health.
Is silicon good for pests and disease?
Silica has also been shown to be an inducer of SAR (systemic acquired resistance) - stimulating natural plant defense responses. These defense responses are effective against many diseases and insect attacks, including powdery mildew prevention, fungal disease protection, and biting insect suppression (mites, whiteflies, etc.) for which it is registered with the EPA for use.
Perhaps the most intriguing facet of silicon as of late is research indicating that silicon plays a significant role in promoting the biosynthesis of various defense compounds. While the exact mechanism is still unclear, it is speculated that silicon forms a ligand of an organic metabolite that results in the promotion of defense genes within the plant. What we do know is that in conditions where plants are facing various stressors, the up-regulation of defense mechanism genes is heavily influenced by the presence of silicon.
General Benefits of Si to Plants
- Increased yields
- Slows transpiration rate
- Regulation of toxic heavy metal elements
- Increased shoot and root density
- Increased cell wall strength (i.e. reduced bud flop)
- Resistance to chewing pests and pathogens (i.e. disease and fungi)
- Resistance to adverse conditions (i.e. cold, drought, salinity, radiation, etc.)
- SAR stimulation - Defense gene promotion/up-regulation
- Overall reduced IPM (integrated pest management) burden
Is silicon good for plant stress?
Both biotic and abiotic stressors are affected, as silicon has been proven scientifically to relieve and prevent a broad range of plant stressors. This is another unique feature inherent to silicon - protection offered across a wide range of stressors that vary immensely in their method of attack on plants. Below are the preventative and protective benefits against biotic and abiotic stressors provided by the use of silicon in plants:
Biotic Stress Prevention
- Protection and resistance to chewing pests
- Protection and resistance to diseases
- Protection and resistance to fungal attacks
Abiotic Stress Prevention
- Increases drought resistance
- Relief of heavy metal toxicity
- Prevention of radiation damage
- Helps prevent nutrient imbalances
- Protective in freezing conditions
- Decreases overall climate stress
- Greatly relieves salt stress
As one can see, there are numerous advantages to employing the use of silicon in any garden. From directly influencing overall health and growth, positive regulation of genetic information, to bolstering plants’ defense mechanisms, silicon is by far one of the most essential, non-essential elements known for plants. The efficacious utilization of this excellent quasi-essential element is critical to the success of any healthy garden. Our team of top-notch scientists at Dutch Master have perfected the formulation of Sila-Guard to provide the precise amount of silicon in the correct form to enable plants to thrive.
How do I use silicon? How do I mix silicon? Always remember to add Commercial Edition Sila-Guard to water first prior to adding any other fertilizers or additives, and stir water well. It’s best to leave Sila-Guard in the water for 5-10 minutes before adding other products - this will help prevent potential fallout/precipitation of your nutritive elements. Sila-Guard is also very effective when foliar sprayed on your plants, as per the instructions on the Feed Charts, to help bolster your IPM and your plants natural defenses.