Share this post
Many factors contribute to cultivation success, and ensuring optimal plant health is the most important of them all. From pests to disease, growers have got their hands full when it comes to protecting their plants. Nutrient lockout is a major concern for many, with the worst-case scenario meaning plant death, and the best-case scenario demanding frequent monitoring and care.
If you have the ability to identify the key symptoms, you’ll be able to both fix and prevent nutrient lockout. Below, we’ll explore what nutrient lockout is, how to spot it early, and the exact steps to fix it before your yield takes a hit.
What is Nutrient Lockout and What Does it Mean for Plants?
Nutrients are what keep your plants healthy and fed, so if you experience a nutrient lockout, your plant is essentially being starved. This ultimately leads to a deficiency in key nutrients or potentially even plant death.
For professional growers and hobbyists alike, nutrient lockout is a critical concern. It will often show itself in the form of stunted growth and yellow, limp leaves. When experiencing nutrient lockout, a plant is no longer able to absorb nutrients from your growing medium – the ‘food’ it requires is locked out from entering the vascular system.
When growing cannabis specifically, nutrients are absorbed into the root via osmosis. If the soil medium or water has a high concentration of salts around the root zone, the plant will suffer in the same way as any other plant with nutrient lockout would. Even when the growing medium contains all of the necessary nutrients, plants still show signs of deficiency because they’re unable to uptake them. As a grower, it’s essential that you know how to avoid nutrient lockout.
Signs of Nutrient Lockout in Cannabis
Knowing the signs and symptoms of nutrient lockout will enable you to act quickly, potentially saving your plant’s health from fatal consequences. If your plants are suffering from nutrient lockout, they may show some of the following signs:
- Stunted growth
- Limp stature
- Yellowing leaves
- Curling leaves
- Scorched leaves
The trouble with identifying what is wrong with your plants is that the signs of nutrient lockout are very similar to general nutrient deficiencies. For example, you could be overwatering or underwatering your plants, and they may show the same symptoms of nutrient lockout.
The only way to be sure it’s nutrient lockout is to check the pH levels of the soil medium or nutrient solution. If it’s outside the optimal pH range (6.0-6.5 for soil), nutrients are likely locked out.
Causes of Nutrient Lockout in Cannabis
As you’re aware, your plants grow by absorbing compounds from nutrients, water, and the atmosphere. However, during this process, your growing medium may accumulate excess minerals over time, which react with your plants. In most cases, nutrient lockout is the result of too many nutrients being present in the growing environment, as opposed to too few! Here are some common factors that cause nutrient lockout:
pH Imbalances
If the pH of the grow medium is too high or too low, essential nutrients may become unavailable to the plant.
Salt Buildup
Over-fertilization or using poor-quality nutrients can lead to a buildup of salts in the soil, which can interfere with nutrient absorption.
Imbalances
Excess nutrients can be an issue. Too much of one nutrient can inhibit the absorption of another, leading to a nutrient lockout.
Biofilms
Biofilms can contribute to nutrient lockout in plants by interfering with nutrient uptake and distribution. They can clog irrigation systems, preventing water and nutrient delivery, and alter the soil environment, reducing the availability of essential nutrients to plant roots.
How to Fix Nutrient Lockout in Cannabis
While this common growing problem is annoying, the good news is that nutrient lockout can be fixed. After you’ve identified that nutrient lockout is definitely the problem, you can follow the steps below to fix it.
- Stop feeding your plants. Overloading the soil medium will only pump them with more nutrients, making the problem worse.
- Flush your plants with pH-balanced water. This will clear the growing medium of excessive salts and essentially rebalance the pH level. If you’re using a hydroponic system, you’ll need to use a fresh solution.
- Allow any soil to dry out completely before you water again. This prevents overwatering.
- Reintroduce nutrients and establish a flushing schedule to prevent mineral buildup.
How to Avoid Cannabis Nutrient Lockout
Despite the fact that you can fix nutrient lockout, prevention is always better than a cure. Focusing on keeping your nutrients balanced and adjusting the pH where necessary should prevent a nutrient lockout from occurring – let’s take a look at that in more detail below.
Regularly Check & Maintain pH Levels
Imbalances in the plant medium’s pH level are one of the leading causes of nutrient lockout. The pH levels should be monitored weekly, or bi-weekly if that’s not feasible, to ensure your plant is growing in the healthiest environment possible.
Monitoring the pH levels doesn’t need to be a costly job – you can get your hands on a basic but highly accurate pH meter for around $50 and, in turn, get peace of mind as to how your plants are doing. By monitoring the pH regularly, any issues can be identified and adjusted before a nutrient lockout occurs.
Choose Your Fertilizers Wisely
Both organic and synthetic fertilizers are readily available, and most growers will have a preference based on their own setup and needs. However, keep in mind that organic fertilizers usually have lower mineral and nutrient levels, which lowers the risk of nutrient lockout. Organic materials are also kinder on the environment, however synthetic options will release nutrients at a faster rate. In either scenario, keeping an eye on your pH levels will allow you to catch any potential problems before they occur.
Clean Your Irrigation Systems
As we explored above, biofilms and mineral buildup can contribute to cannabis nutrient lockout. To remove biofilm and ensure all parts of your growing set-up are working as they should, your irrigation systems should be cleaned. The ideal cleaning method is to use a chemical-free solution like Clear Flow™, which is safe for use throughout all stages of plant production and works seamlessly in both direct-to-drain and recirculating systems.
For growers who need a more robust solution in securing optimum plant health, Clear Zona™ is essentially the one-stop shop for clearing away biofilm, sludge, green water, plant debris, and more. Taking a two-pronged approach, Clear Zona™ uses a proprietary combination of catalytic enzymes (Part A) and beneficial microbes (Part B) to naturally degrade biofilm and other organic debris.
Important: Clear Zona™ is not compatible with chlorinated or chloramine-treated water unless the water is allowed to sit for 24 hours to let the treatment off-gas. If immediate use is required with treated water, Clear Flow™ is the better choice.
Not sure which one to pick? Read about the differences between the two here.
In summary, keeping your water flow free from unwanted buildup is vital to the success of your greenhouse or grow room, going some way to fix nutrient lockout. Both of our solutions have been designed to boost yield by delivering high-quality irrigation water.