Selecting the right organic hydropnic nutrient for your hydroponic or soilless system is a big decision for your greenhouse, vertical farm or indoor farm. With so many factors to take into consideration when assessing the spectrum of options that exist, growers can find themselves at cross roads. We wanted to relieve this guesswork for you and provide a “map” of sorts in the form of questions that we often encounter. In reality, every indoor grower should ask their nutrient supplier the same.
For this publication, we will focus on identifying how the nutrient you’re selecting could affect your system’s water quality.
Assessing The Quality of Water in Your System
It’s common for many of us to think that the quality of our local water supply is sufficient for growing crops. If we can use the hose in our garden to water our plants there, shouldn’t we be able to use that same water source for our soilless growing system? Unfortunately, as many of you may agree, that’s not the case. Poor water quality can lead to nutrient deficiencies, crops growing much slower than they should, and a variety of additional factors. Add onto this the need for nutrients within the water reservoir and a range of other questions pop up.
This is where we can help.
What can an indoor grower ask their nutrient supplier to gain confidence that organic hydroponic nutrient is right for their growing needs?
What is the average EC of the water in a soilless system after using your nutrients?
An EC meter measures the nutrient levels of the water in the soilless system. Typically, growers want their water to have an EC of 0 ppm prior to nutrients being added to their water reservoir or tank. Afterwards however, depending on what is being grown, the nutrient must reach a desired or targeted EC ppm (parts per million) level. For example, tomatoes and cucumbers are known for producing mildew if the EC is too low. The right nutrient for your crop will be able to hit that “sweet EC spot”. The chart below from IG Works provides a helpful example for growers to reference.
What is the average pH of the water in a soilless system after using your nutrients?
The topic of pH levels of organic hydroponic nutrients affecting water quality isn’t new to many growers. In a nutshell, the pH measurement post-inclusion of nutrients indicates the hydrogen ion concentration in the system. Most soilless systems do best when their water sits within the 5.5-6.5 pH range. Each increase or decrease on the pH scale represents a 10-fold change in the acidity/alkaline level. Therefore, a small change in the pH of your water will lead to a huge impact on your plants’ ability to absorb nutrients. This means that small changes in values are large changes in pH. For example, a value of 7 is 10 times higher than 6 and 100 times higher than 5. Now, when the wrong nutrient is added to the water and the pH gets thrown off, it can lead to a “nutrient antagonism”. In other words, when there’s too much of a certain nutrient, the plant will absorb more of it compared to the other nutrients in the water. The table below by Penn State’s Pennsylvania Nutrient Management Program shows how the effect of pH, and thus nutrient antagonism is one that growers should be aware of when it comes to the water quality of your soilless systems.
This is, of course, not an exhaustive list. But we hope this has given you some food for thought. Now, the question is, “Can an organic hydroponic nutrient protect the water quality of your reservoir?”. The answer: Yes. We can show you how.
* While this is by no means an exhaustive list, we hope this will help as many indoor growers as possible – because a more informed grower means a healthier food system!
* For a list of our organic hydroponic nutrient’s FAQs, click here.