No products in the cart.
Today, we’re exploring a powerful yet often overlooked tool in the professional grower’s toolkit—salicylic acid. Whether you’re growing leafy greens, herbs, or fruiting crops, understanding how this compound works can help improve plant health, disease resistance, and even flavour.
Salicylic acid was originally extracted from willow trees (Salix), hence the name. You can also find it in wintergreen, meadowsweet, and Gaultheria species, typically in the bark or roots.
In plants, salicylic acid plays a key role in defence mechanisms, particularly in activating systemic acquired resistance (SAR), a natural response to pathogens like viruses and bacteria.
When a plant is attacked by a pest or pathogen, salicylic acid is released internally. This triggers a cascade of protective responses:
Unlike other elicitors like seaweed extract or chitosan, salicylic acid is systemic—meaning it moves throughout the plant, not just staying where it’s applied.
Hydroponic growers face unique challenges when it comes to disease prevention, particularly with viruses and pathogens. Using salicylic acid (SA) proactively can help:
Caution: Once a plant is infected with a virus, applying salicylic acid will not cure it. At that point, it’s best to dispose of infected plants and thoroughly sterilize tools and equipment.
A fascinating derivative of salicylic acid is methyl salicylate, a volatile compound that plants release into the air to warn neighbouring plants of danger—activating their defences much like ethylene gas.
This natural communication between plants may sound like science fiction (think The Happening film), but it’s a real and studied phenomenon in plant biology.
Yes—indirectly. Salicylic acid stimulates the production of secondary metabolites, which include many of the compounds responsible for flavour, aroma, and even colour in fruits and vegetables. These defence compounds are not always active, but SA can trigger their formation during flowering and fruiting stages.
So, if you’re aiming to enhance flavour profile in hydroponically grown crops—especially herbs and fruits—salicylic acid may be worth experimenting with.
Salicylic acid is also widely known for its role in acne treatment and chemical exfoliation, which can cause confusion when marketed for agricultural use. Some buyers mistakenly attempt to use high concentrations on skin, leading to serious irritation.
Additionally, a few turf managers have attempted to use it to repel worms on golf greens, but this is not an authorised use.
You can apply salicylic acid in hydroponics via:
Some commercial products contain SA as a biostimulant. A few brands like BioGreen in the UK may offer it, but if you’re looking for a high-concentration standalone product, we offer one specifically for growers.
Note: In the U.S., availability may vary, but pure salicylic acid is often sold through agricultural suppliers and may need to be diluted appropriately for safe use.
Interestingly, aspirin (acetyl salicylic acid) has long been used to prolong the life of cut flowers by reducing wilting and petal drop. Salicylic acid works similarly and may even be more effective, acting like a “key” that fits perfectly into the plant’s natural defense pathways.
Salicylic acid is more than just a skincare ingredient—it’s a plant defense powerhouse that can help hydroponic growers:
If you’re serious about dialling in your hydroponic system, salicylic acid deserves a place in your plant health protocol. Want to know more? Feel free to get in touch or explore our concentrated SA product line.
Article by Dr Russell Sharp
If you would like to keep up to date with subjects just like this, you can listen to both our podcasts! Links can be found bellow:
Hydroponics Daily Podcast: https://open.spotify.com/show/207T7p7fw9sPjINfSjVXW2
Cereal Killers Podcast: https://t.co/eSEbBkTVHl