How to Cure Nutrient Lockout in Cannabis

Nutrient Lockout in CannabisNutrient lockout occurs when a cannabis plant is unable to absorb certain nutrients, even if they are present in the growing medium. This can lead to a variety of issues, including stunted growth, nutrient deficiencies, and even death of the plant.

Causes of Nutrient Lockout in Cannabis

Nutrient lockout can be caused by a variety of factors, including pH imbalances, over-fertilization, poor soil quality, or environmental stressors. One of the most common causes of nutrient lockout is pH imbalances in the growing medium. When the pH level is too high or too low, it can prevent the plant from absorbing certain nutrients.

How to Test and Adjust pH Levels for Cannabis Plants

To test the pH level of your growing medium, you can use a pH meter or pH testing strips. Most cannabis plants prefer a slightly acidic environment, with a pH between 6.0 and 6.5. If the pH level is too high or too low, you can adjust it using pH adjusters or pH-up and pH-down products. Be sure to follow the instructions carefully to avoid overcompensating and causing further imbalances.

Flushing the Growing Medium to Cure Nutrient Lockout

If your cannabis plant is experiencing nutrient lockout due to over-fertilization, you may need to flush the growing medium with water. Flushing helps to remove excess nutrients from the soil or hydroponic system, allowing the plant to absorb nutrients more effectively.

To flush your growing medium, water your plants with plain, pH-balanced water. Use enough water to saturate the growing medium and flush out any excess nutrients. Repeat this process until the runoff water is clear.

Using Chelated Nutrients to Improve Nutrient Absorption

Chelated nutrients are specially formulated to be more easily absorbed by plants, even in environments with high pH levels or other nutrient lockout issues. Chelated nutrients contain nutrients that are bound to organic molecules, making them more readily available for absorption.

When choosing chelated nutrients, be sure to read the label carefully to ensure you are using the correct formula for your plants’ stage of growth.

Adjusting Growing Conditions to Prevent Nutrient Lockout

Environmental stressors, such as high temperatures or low humidity, can also contribute to nutrient lockout. Make sure your plants are growing in optimal conditions, with appropriate lighting, temperature, humidity, and air circulation.

Maintain consistent growing conditions and monitor your plants regularly for any signs of stress. Adjust the growing conditions as needed to prevent nutrient lockout and promote healthy growth and development.

Tips and Tricks for Preventing Nutrient Lockout in Cannabis Plants

To prevent nutrient lockout in your cannabis plants, be sure to test your pH levels regularly, use high-quality nutrients, and provide optimal growing conditions. Avoid over-fertilization, and flush your growing medium as needed to prevent nutrient buildup.

Common Nutrient Deficiencies in Cannabis and How to Address Them

Nutrient deficiencies can be caused by nutrient lockout, but they can also occur due to a lack of nutrients in the growing medium. Common nutrient deficiencies in cannabis include nitrogen, phosphorus, and potassium deficiencies.

To address nutrient deficiencies, you can use nutrient supplements or adjust your fertilization schedule. Be sure to identify the specific nutrient deficiency before making any adjustments.


Nutrient lockout can be a frustrating problem for cannabis growers, but it is one that can be easily prevented and cured. By testing your pH levels regularly, using high-quality nutrients, and providing optimal growing conditions, you can promote healthy growth and development in your cannabis plants. With a little bit

5 Responses to “How to Cure Nutrient Lockout in Cannabis”

  1. sourdo

    My recent experience with nute lockout was the failure to let enough water run off and empty the trays. At 4 months I was getting Ca deficency and tip burn. Since 4 of my plants went hermie (stress?) and the buds were nice and stinky I started to flush with plain ph’d water for a week or so. Mistake. My tight stinky buds, almost overnight turned very green and hay smelling, and man did they fluff out. One plant, the trichomes disappeared overnight! The plants went into a growth veg like spurt. I wacked ’em down, some nice colas but damn the green smell, hope I can cure that out. Some of the better buds have a fruity smell to them, weird. I just smoked a piece of green fluff quick dried, 4 hits I was surprised on the high so not all is lost.


  2. Mick

    I am currently suffering 5 babies with nutrient lock, i have aqua mix soil which has the first 2 week nutriens already in, me being silly started giving them nutrients after the first week in the pots…
    They been in veg stage for 3 weeks now and are only 6″ tall usualy after 3 week would be at 30″ tall on average.
    Ive flushed them with 10°C fresh tap water then added superthrive to give them the boost they need while the soil dries out… i’ll give it just water ph’d @ 6.2 from now on for 2 weeks
    For thoses who dont know about “Superthrive” its a substance you add and it numbs the roots and allows them to take in what they need without getting shock, root rot etc…
    Apparently it enhances the growth too so i’m going to give them 2 week more to hopefully see some changes…

  3. tom the ripper

    I’m having a similar issues. Now,I will star by saying I recently found out that your supposed to let water sit to evaporate clorine that may be in the water.( I think my city uses more flouride then chlorine) . Im sure this doesn’t help my soil Ph level. Now; back to it.
    I over feed plants. I think… I gave them Happy Frog 5-5-5 @ half the recommended dose. I did not think about it when i then waterd the plants with Fox Farms Big Bloom liquid add ( also dosed down). As a resualt my largest female began to show signs of Nitrogen burns (pale yellow leaves curling with necrosis and dark red stems ). At first i began using baking soda dosed @ 1Tbls.\4Gal. And the signs only worsened. I later found out that baking soda turna to salt when broken down . In a panic because of of her larger fan leaves were dying and buds were starting to look sick. I began to add copious amounts of tap water to the soil. Again the symptoms presented looked as if the buds were beginning to be affected (at that time the buds were entering their 2nd phase of flower or possibly ending the 1st phase). I repotted all plants as 3 clones were also affected by the same mistake ( 3 clones were far smaller then my oldest plant). I use a mixture of Fox Farms Ocean Forest Perlite for better drainage with a mixture of: [3:1]. (when i repotted them i washed the root systems of old soil as it had a PH of 4.5)
    The oldest plant only seems to be displaying symptoms of: Dead brown patches on leaves and still has dark red stems. Bud growth seems to have continued. However, smaller limbs have seemed to suffer, as her cola’s pistels dry- brownish, and small.
    I have 1 clone that was “Monster Cropped” ( reverting a clone in flower back to veg). Her limbs have many wild shoots and tons of bud sites. She has very odd leaf growth some with three and many with only one. She is my favorite but she is showing signs of over watering i think but there are symptoms of nroken leaves and brown spots as well. (im aware this may be residuals from over nuitreancing the soil) all she had was the Fox Farms Big Bloom. I didnt know i was suppose to let my water sit to evaporate the clorine in the water. I do use city tap water but do not know the PH. ( This may be my problem with my soil getting too salty)Back to the clones lol. She has firm but droppy leaves, very light green in color, and again dead/dieing brown spots.
    Her very small sister seems to be doing veey well she was a tiny clone and is now in the end of her first flowering phase. Her leaves are both dark geen and pale-yellowish but no dead spots just very small lol.
    The last clone seems to be doing better she is recovering from similar issues. I used dolomite lime with somthing called Advanced Soil Tech lol idk it was supposed to work as soon as ir contacted water.

    Im kinda at my limit of what i know to do im looking for suggestions ao i can fix this.

    – Thanks guys\girls, TomThe”Ripper”

  4. Tricks

    Tom The ”Ripper” What up bro, just saw your post, by now you have harvested, I hope you figured out your having PH problems ..I’m going to read the post again but the one thing that jumped out was your run-off being ” 4.5″!!! Brother man, 6.2 to really 6.7 is the sweet spot….4.5 is far to low and will cause a number of problems.

    As far as feeding goes, with seedlings and clones I always let them use up most the nuts in the potting soil (FF Ocean Forest ) before I start feeding. Always be sure you get a good run-off, at least when watering, helps avoid lock-out, another thing that helps, especially on longer grows is to add a drop of dawn dish soap to your water, it helps keep the soil loose. Hope this helps! Happy Growin..Peace!

  5. jf

    I’m in3rd week of bud and have lockup in hydro What u recommend

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