What is Gypsum?

Gypsum is a natural source of both Calcium and Sulfur (Calcium Sulfate) that corrects soil sodicity (too much Sodium). It improves the Calcium to Magnesium ratio of soil which in turn loosens the soil improving water infiltration, soil structure and Oxygen content.
The Sulfur in our Gypsum will enhance crop flavours and aromas, but also plays a vital role in nitrogen fixation (Sulfur is present in the important nitrogenase enzymes which contain a Fe-Mo-S cluster) and is used as a catalyst for many vital plant processes. Sulphur is also involved in proper function of the immune system of plants via having ample glutathione to combat oxidation stress. 

What are the benefits of Gypsum for Plants?

  • Calcium is the workhorse of the plant. It shuttles other nutrients around the plant, Its availability to the plant is of incredible importance.
  • Sulfur is required in the production of both terpenes and resin. Having an abundance of Sulfur will allow the for maximum terpene and resin production.
  • Improves soil tilth.
  • Improves water infiltration.
  • Helps prevent and correct soil sodicity ( >15% Na in cation exchange complex ).
  • Reduces surface crusting.
  • Increases yield and flavour.
  • Facilitates intensive transportation of macro-molecules around the plant during bloom. 


How do I use Gysum?

Gypsum can be top-dressed, mixed into soil or used in waterings, with NO negative impact on plant health. Gypsum can be applied in heavy doses with no issue and provide an intermediate length source of calcium and sulfur. Gypsum has a solubility of aprox 2g/ L at room temperature allow it to be used as immediately available organic source of Calcium and Sulfur.

  • We recommend at least 2 cups of Gypsum per 25L of Medium.
  • 1 Cup per plant can be used mid cycle to treat calcium issues.


(SKU: 129305)

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