Like all flowering plants, marijuana is supposed to smell wonderful and flowery. If the female marijuana you’re growing start to smell like rotten eggs, then you know you have a problem and it might just be root rot.

What is Root Rot?

Root rot is commonly caused by a fungus-like organism called Pythium. Although it is most often found in hydroponic systems, it can also affect plants that are in soil or other planting mediums.
The same symptoms of root rot caused by over watering your cannabis plant can be found in root rot caused by Pythium. It will look like your plant has various kinds of nutrient deficiencies on its leaves. In a sense it does because the roots cannot properly absorb the nutrients it needs, even though those nutrients are actually abundant.

How Do I know If I have Root Rot?

The plant will look stunted. Your leaves will become yellow, wilting, and slowly die out. One of the telltale signs of root rot are particularly slimy brown roots instead of the common healthy and firm white or off white roots. The first, unmistakable sign of root rot is an overpowering stench. YFlear take another whiff of it.

Cannabis leaf

Cleanliness Is Key!

Pythium attacks stressed plants first; gaining entry into the plant by damaged plant tissues. Roots with injuries from insects can also provide an entry site for the pathogens through the feeding wounds. Pythium usually attacks the root tips first and then works its way upward in the root system.

Disinfect Everything

Because root rot in hydroponic systems is the most common, I’m going to help you prevent it from happening there in the first place. Cleanliness is key! Disinfect all your growing equipment extremely thoroughly before you start growing a new crop every single time. Keep your area clean and free from dead cannabis leaves, roots, or other debris to prevent bacteria from growing. Sterilize equipment shared between tanks like pH meters. Use filtered water, or if you’re using well water or untreated water have it checked for microbes.

Change Your Water Frequently

Change your container water regularly to prevent stagnant old water from overproducing bacteria. Try to do this about once a week; don’t wait longer than 2 weeks to do it. Having new water, and the nutrients that come along with it, will keep your plants healthy. The water should be at a stable pH level. Somewhere between 5.5 -6.0 pH is good. You should keep the temperature between 65-70F (18-21C). Take into account that submerged pumps can increase the temperature of the water.


Cover Your Reservoir

Cover your reservoir to avoid light and debris from getting into it. Also, try to avoid transplanting from soil into a hydroponic system. Dirt within the roots can be a haven for pathogens, so start with a soil-less medium for seed starting.

Hidro roots

Hydrogen Peroxide

Follow these cumbersome but nonetheless ‘easy’ rules and you might actually stand a chance to fight off root rot. If you’re already fighting root rot, I’m sorry to say that in many cases it’s fatal and you may have to start a fresh batch. Although if you’ve just noticed that your roots have a mild case of root rot then introduce fungicides created to treat Pythium into your system.

The Debatable Use of Hydrogen Peroxide

There are some other debatable practices that may help you if you are in a root-rot-rut. Some growers have had success with using hydrogen peroxide, others say it’s only a temporary solution and they prefer other store-bought root treatments.
If you want to try the Hydrogen Peroxide treatment, then take your plant out of the system and cut off damaged roots. Soak the roots in a container with a strong Hydrogen Peroxide solution repeatedly until the diseased parts have come off. A 2:1 solution of water to hydrogen peroxide (using a 3% hydrogen peroxide solution) should do the trick. It is imperative that you sterilize your equipment before replacing your plants.
Your pots, hoses, reservoir, everything needs to be sterilized with bleach or a strong peroxide solution and rinsed very well. When you are ready to put the plants back add an anti-Pythium additive and fresh nutrients to your reservoir. Keep your temperature on the low side and keep an eye on the plant in the next week to see if it’s growing new, beautiful, and firm white roots.

Heathy roots

What If You Cannot Fight the Root Rot?

If your babies are just not making a comeback, then it’s time to say goodbye and learn from your mistakes. Remove all the affected plants; do not compost them as the Pythium microbes will continue to live in the roots of the infected plants. Again, sterilize the hell out of your equipment, get rid of all the contaminated water and don’t look back! Start afresh, you can do it, the next batch will be well worth it and this will never happen to you ever again, right?