One of the most common problems faced by indoor cannabis growers is nutrient lockout. Sometimes referred to as “lockup” or simply “lockout,” nutrient lockout is a common occurrence, but one which can leave a beginning grower scratching their head and wondering just what happened to their plants.
Often misidentified as a nutrient deficiency due to the corresponding symptoms, nutrient lockout can be difficult to identify correctly. Fortunately, once identified, the problem can be reversed, and the plant reinvigorated so long as it is handled in a timely manner.
What is Nutrient Lockout?
Nutrient lockout occurs when a plant’s roots and growing medium become overly-saturated with excess chemical nutrients and fertilizers. Because many nutrient lines (especially hydroponic nutrients) are salt-based, these salts can accumulate in your plant’s root zone or in the growing medium. An excessive buildup of salt-laden nutrients can cause nutrients to bind to one another and lead to your plant’s inability to uptake the nutrients provided by the solution through its roots.
As a result, the plant cannot use the available nutrients, despite continued feeding and watering. Continued feeding during nutrient lockout can actually make the problem much worse. Hydro grows, especially those utilizing coco coir or Rockwool mediums, are especially susceptible.
How to Identify Nutrient Lockout in your Cannabis Plants
Nutrient lockout can be challenging to detect and properly identify because its symptoms so closely resemble a nutrient deficiency. Symptoms typically include:
- Weak, flimsy stalks
- Droopy, discoloured foliage
- The appearance of being underfed
- Stunted growth
- Yellowed or yellowing, curling leaves
It is easy to see how nutrient lockout can be mistaken for a nutrient deficiency. This common misidentification leads many growers to increase the levels of nutrients in their solution, in turn making the problem worse. It is essential to take several proactive steps to identify and prevent nutrient lockout before it devastates your plants.