How To Identify And Prevent Root Rot On Weed Plants

Root rot is a fungus that goes after your marijuana plants’ precious roots, especially when they have already been weakened due to stress, diseases, a lack of nutrients and damage from other causes.
Root rot (pythium) is technically a parasite, and it targets seeds or seedlings most of all. This means that your younger plants are most at risk and are quite vulnerable to root rot. The tricky thing about root rot is that it grows rapidly, and it spreads via spores that are too tiny to see. The miniscule spores are what are going to lead to a problem with your entire marijuana garden when it started with just one little plant. Any kind of growing system can have affected plants, and it will be oddly picky when decided “who” to go after.
The spread of root rot happens below ground via water. This water travels between root systems, and the root rot spores travel with it. It germinates on the go, meaning it will be ready to grow and multiply by the time it reaches the next root system. This is its method for going from just one affected plant to your entire garden being in trouble. Find out how to identify and treat root rot before it’s too late.

Root rot symptoms

Root rot is difficult to notice, due to the fact that it begins underground and is basically invisible until it starts having negative effects on the plant itself. It will be hard to miss once your plant has wilting, yellowing leaves with browning along the edges. You won’t know for sure that it is root rot until you have looked directly at the roots – otherwise it could be any fungal infection.

The roots will feel soft and appear rather watery and discolored. If these symptoms are on your plant’s roots, it without a doubt has been attacked by root rot. Eventually the roots will start to lose their outer layer and the interior (which appears stringy in texture) will be able to be seen.

If your plants are growing in a hydroponic system, detecting root rot shouldn’t be difficult (since the roots are always visible). With soil-based growing systems, however, all you need to do is dig into the soil and take a look at the roots. You will also be able to smell them. If they smell like mildew or rotting, it is likely root rot. If they look brown-colored instead of the normal cream or white color, it’s probably root rot. Regardless, make sure to check the roots before you decide you need to treat your plant for root rot, as the true infection could be something else altogether.

The leaves of your plants will look burnt, brown, yellow, or white. They will clearly be dying, and some will fall off your plant. Nutrient deficiency symptoms are not uncommon with root rot since roots can’t function and absorb normally. They will also be absorbing a smaller amount of water than normal, so if you notice a decrease in water absorption, then you should take a look at the roots. Not sure if your plants suffer from root rot?

Combating root rot

Root rot is bet fended off before it ever happens. This is done by keeping your whole garden happy and well cared for. The soil should never have too much water trapped in it, and there should be plenty of nutrients for your plants’ roots to absorb. In a hydroponic system, cleanliness is the number one way to make sure that root rot does not become a problem. Peroxide can be a good way to do this, but be aware that it kills all bacteria – even the beneficial bacteria. If you do encounter a root rot infection, it will be impossible to stop the spread to your other plants.

Root rot prefers moisture and warmth, so temperatures of 70 degrees or more that also include high levels of humidity are the prime time for root rot to develop. Use compost instead of too much fertilizer, as long as the compost was created and aged the right way.

Root rot often accompanies pests (or vise-versa), so try to keep those pests away from your precious marijuana plants. Overwatering your plants can also contribute to making the environment into a high-risk environment for root rot. Be sure that the soil dries completely before you water next time.

If you want something effective, try buying root controls – but make sure they include “root rot” as one of the things they fight off. You can also use copper treatments, oil sprays that include clove, coriander oil, sesame oil, and Trochoderma, which is an example of a good kind of fungus.

Once root rot is discovered, plenty of growers simply discard the entire plant rather than going through the hassle of trying to rid it (often unsuccessfully) of root rot. There are some things you can do besides throwing out the entire plant, though. Whatever treatment you choose, it will need to go straight to the “root” of the problem – in other words, apply it directly to the roots. The environment that the root rot is currently thriving in will also need to change – if this is impossible, it’s better to discard the plant because the root rot will never go away for good.

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Keep in mind that, even if you rid your plants’ roots of root rot, the damaged roots themselves will not heal. Instead, new roots will begin to form – and this is how you know that your plant is recovering. Leaves function in the same way – new growth is the measure of how healthy your plant is.

Root rot & hydro systems

If root rot has gotten into your hydroponic system, you are going to need to ensure that you rid the system of it so that it never returns. The grow room itself is going to need a drop in temperature, which will fortunately also lower the water temperature.

The lower the temperature, the more oxygen can be in the water at any point, and oxygen is a crucial fighter of root rot. It also will make your plants grow extra fast. Root rot affects hydroponic systems when the temperature is 72 degrees Fahrenheit or warmer, so keeping it lower than this will keep the root rot away.

Another way to increase the oxygen of the water (and the safety of the root systems) is to add an air pump and some air stones. The air pump will agitate the water’s surface, and that adds more oxygen. Adding in beneficial bacteria is a further way of equipping your plants with the tools to fend off root rot.

Hydroponic systems need to have their reservoir water replaced every two weeks at minimum. This will increase your plant’s ability to access more nutrients, and will, therefore, stop your marijuana plants from having too much or too little of a nutrient. It also keeps the dead matter out (which you should also do by hand yourself), which is where bacteria love to live and grow.

To further prevent root rot, make sure the grow lights are not too close to the reservoir water and your plants’ root systems. This is simply because the light will add in too much heat, making a nicer home for root rot. You should also clean out every piece of equipment thoroughly before even putting your plants into the hydroponic system, therefore killing any prevailing bacteria.

If you can, try to avoid using hydrogen peroxide for root rot. This would only work for a day or two, meaning the treatments would need to be requent and it would also kill off any of the good bacteria that your plant needs.

Marijuana symptoms list

Leaf Color:
– Brown or burnt edges
– Pale color
– New growths: yellow
– Lower, older leave: yellow
– Brown or dark-colored spotting

Leaf Symptoms:
– Burnt leaf edges
– Burnt leaf tips
– Death of leaf tips
– Curling under of leaves
– Curling upward of leaves
– Spots
– Old leaves falling off
– Slowed growth
– Abnormal growth
– Wilting or drooping leaves

Plant Symptoms:
– Weak stems
– Slowed growth
– Wilting or drooping of entire plant

Root Symptoms:
– Brown
– Smelly
– Mushy
– Slowed growth

Root rot is more commonly found in indoor growing systems. This means that if you are an indoor grower you are going to need to be prepared to actively prevent root rot from getting to your plants from the very beginning. Whether you’re growing your plants indoors or outdoors, be sure not to overwater, and keep special tabs on the rate of water intake.

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