When I first started with hydroponics, my focus was solely on getting the system to work—making sure the pumps ran smoothly, the water circulated properly, and the plants had everything they needed. I didn’t pay much attention to the chemical details. But as I progressed and experienced a few failures along the way, I learned the hard way that one of the biggest reasons for hydroponic systems failing is pH imbalance. Low pH, in particular, can wreak havoc on your plants. In this article, we’ll explore why low pH occurs, its effects on your plants, and how you can prevent it using tools like the Growee pH Controller.
What Is the Natural pH of Water?
In most cases tap water has a pH level of around 7.5, which is considered neutral. However, depending on the water source, pH can vary. For example, rainwater often has a lower pH due to the absorption of carbon dioxide from the atmosphere, while treated tap water may be slightly alkaline because of added chemicals.
In larger cities, which often rely on multiple water sources, pH levels can differ across various section of the city. Water supplied to one part of the city may come from a different reservoir or treatment facility than another part, leading to variations in pH. In general, though, drinking water usually falls between 7 and 8 on the pH scale.
Why Is the Source of Water Important in Hydroponics?
In a hydroponic system, water acts as the primary medium for delivering nutrients to your plants. The quality of the water used directly impacts the overall health of your plants. Unfiltered water can contain impurities, excess minerals, and harmful chemicals that disrupt nutrient absorption and growth.
For example, municipal water is often treated with chlorine or chloramine, which, while safe for humans, can harm plants. Similarly, water with a high concentration of dissolved solids (measured as Electrical Conductivity or EC) can introduce excess minerals that may be detrimental to plant health. Ensuring that your water source is clean and free of unwanted minerals is crucial for the success of any hydroponic garden.
Why Is the pH Different in Water Compared to Soil?
In soil, organic matter, microorganisms, and minerals create a buffer that makes the pH levels stabilised. The soil is a natural buffer that tolerates pH fluctuations, which makes growing in soil more forgiving. However, one downside to soil is that it’s very difficult to change the pH significantly once it’s established. This means you can only grow specific plants in specific types of soil. For example, if you want to grow blueberries, which require acidic conditions, you’ll need to ensure the soil has a low pH level.
In hydroponics, plants rely solely on water and nutrient solutions, so pH changes happen more rapidly. This makes it crucial to monitor and adjust the pH regularly to avoid harming the plants. While hydroponics lacks the buffering capacity of soil, the ability to control pH more easily allows you to grow a wider range of plants with varying pH requirements in the same system.
What Happens to Plant Roots When the pH Is Too Low?
When the pH of your hydroponic system drops too low, for most plants below 5.5, the water becomes more acidic, leading to several problems for your plants’ roots:
- Nutrient Lockout: Roots can no longer absorb essential nutrients like calcium, magnesium, and potassium. This leads to deficiencies, which can cause discoloration, stunted growth, and poor overall plant health.
- Root Burn: Acidic water can burn the delicate root tips, causing them to die back or become stunted.
- Increased Disease Risk: Low pH levels weaken the plant, making it more susceptible to root diseases like Pythium (root rot), which thrives in acidic environments.
How Can We Know If the pH in a Hydroponic System Is Low?
One of the easiest ways to keep track of pH in your hydroponic system is by using real-time monitoring tools like Growee. The system has a pH probe that sits right in the water and constantly monitors the pH. It’s all connected to the cloud, so you can check measurements and see trends in a simple, clear way. This setup helps you catch pH issues early and make adjustments before things get out of hand, ensuring your plants stay healthy and avoid problems like nutrient lockout or root damage.
How Can We Change the pH of Water Using a Controller?
In hydroponics, keeping the pH in check is crucial for healthy plants. You can adjust it by adding pH up (to make it more alkaline) or pH down (to make it more acidic). That’s where a pH controller like Growee comes in handy. It automates the whole process. With Growee, a pH probe constantly monitors the water, and when it senses a change, the system automatically adds just the right amount of pH solution to keep the levels in the ideal range, typically between 5.5 and 6.5.
The best part? Growee does all this without you having to constantly test and adjust the water yourself. It keeps things stable and makes sure your plants are always in the right environment to thrive.
The best indication that your pH is off is brown or mushy roots
When the pH is too low, it can cause root damage that shows up as browning, slimy, or decaying roots. Often, these roots will also develop a foul smell, which is a clear sign of rot. This happens because low pH prevents the roots from absorbing nutrients properly, and it creates the perfect environment for harmful bacteria to thrive.
Conclusion
Maintaining the correct pH level in your hydroponic system is key to growing healthy, thriving plants. Low pH can lead to nutrient deficiencies, root damage, and disease, but with tools like the Growee pH Controller, you can easily monitor and adjust pH levels. By automating the process, you save time and effort while ensuring that your plants are always in the right environment for optimal growth.
