One of the essential parts of growing cannabis is to take care of its roots. Healthy cannabis roots equate to a robust plant.
A cannabis plant is like a complex set of gears — several gears must work together to ensure the plant grows and thrives well.
One of the most vital gears is the roots — if the roots are healthy, the plant will grow healthy.
Or, die quickly if you ignore the roots.
Even before starting your project of growing cannabis plants, you need to ensure you plan it in such a way that the roots can thrive and encourage plant growth while avoiding any problems.
This article teaches about the key to growing healthy cannabis roots for your plant.
What Do Healthy Cannabis Roots Look Like?
Healthy roots are unmistakable — they appear white, almost milky, in color, and lack a strong smell.
Healthy roots grow into a root ball throughout the medium in a container filled with soil and support the plant throughout its life cycle. They are responsible for great yields.
On the other hand, if you notice the roots are dark brown, discolored, slimy, or stinky, you are dealing with an unhealthy root system.
How to Keep the Roots Healthy?
If you want to keep your roots milky and clean, you must take some measures. Here are some tips for keeping your roots healthy and ensuring terrific plant growth.
- Get Good Seeds to Start With

All the following tips are pointless if the seeds you purchase are low quality. Many growers don’t know this, but the seeds’ quality plays a major role in your plant’s overall health. Thanks to genetics, which is why we pay special attention to all our American genetics in our catalog.
Whether you prefer to grow a photoperiod cultivar like the Hypno Zkittlez or an autoflowering strain like Cream-Brulee Auto, you can rest assured that the genetics support great root growth hefty nugs.
Thus, you must always start with high-quality seeds harvested from healthy plants. Your best bet is to choose a reputable seed bank that has strict standards for harvesting seeds and provides you with all the information required to germinate and grow them.
You can also talk to other growers to know more about how they grow their plants. It’s always better to learn from others’ mistakes when growing cannabis.
- Choose the Right Container Size

Next, you must choose the right container for your plant from Day 1 if you are growing in soil. This is because the roots grow quickly during the initial stages of the plant.
If the container size is wrong, they may either not grow well or have too much room to grow, which can also be harmful. If the container is too small, the roots fail to develop fully and can become constricted within the pot, also known as “root bound.”
A small container doesn’t allow a healthy, big root ball to develop. It may further cause many issues since they cannot absorb adequate nutrients for the plant to grow properly. Needless to say, the plant may experience nutrient deficiencies, lanky or stunted growth, health problems, etc.
On the other hand, if the container is too large for the root ball, the nutrients and water may fail to reach the roots properly. So, you’d have to compensate for this by adding more nutrients and water to the soil, which can lead to “hot” soil that can cause a nutrient burn.
Note that the container’s size depends on your plant’s specifications. For some strains, a smaller container of 3 gallons works well, but other strains may require a bigger container. Choose the one that is fit for your cannabis strain.
- Ensure Adequate Oxygenation in the Substrate

Roots absorb oxygen, which is crucial for ATP (Adenosine triphosphate) formation. ATP is responsible for transporting energy throughout the plant. So, if the roots are starved of oxygen, the plant experiences a lack of energy and starts starving.
If you are growing in soil, you must ensure you keep the soil oxygenated by properly watering the plant. Avoid over watering, which may drown the roots (more on this below).
You can also use fabric pots instead of conventional pots. Fabric pots, or smart pots, are made of breathable fabric that improves air circulation within the substrate.
You can also add per lite to the soil to increase oxygenation — the per lite mix helps keep the soil fluffy and light.
The roots will be constantly immersed in water in a hydroponic setup, so you need to aerate the water using air stones.
- Fine-tune the Temperatures

While cannabis can grow in all kinds of climates, it grows best at 65°F to 75°F (18°C to 24°C). And the right temperature is crucial for healthy root growth. Here are the temperatures you should stick to:
- During the vegetative stage: 72°F to 82°F or 22°C to 28°C
- During the early flowering stage: 68°F to 78°F or 20°C to 25°C
- During the late flowering stage: 65°F to 75°F or 18°C to 24°C
And it is quite easy to regulate the substrate temperature to optimize growth. In a soil-based system, you can place an intake fan under your canopy and an exhaust fan above it to promote aeration around the root zone to keep the roots cool while preventing any hot spots around the plant.
You should also invest in hygrometers that monitor the temperatures and humidity around your plant.
Regulating temperatures can be difficult in an outdoor setup unless you use a polytunnel or greenhouse. Instead, you can simply insulate the topsoil with crops like clover or mulch to keep the temperature under control.
In a hydroponic setup, you can maintain the temperatures by painting the reservoir white, regularly adding ice to the reservoir, or investing in a hydroponic chiller — the latter is an expensive investment but it is also the most reliable.
- Maintain a Healthy Watering Routine

Water is crucial for your plant’s root development. But more water does not mean better growth — a mistake many new growers make. Roots grow in search of water, so you need to ensure your water is enough, but too much can drown the roots and cause oxygen deprivation.
So, if you are growing in soil, you need to gradually increase watering for your plant and watch out for any signs of over watering. Ideally, you should water your soil-based plant when the top inch of the soil is dry to the touch. Generally, this means you will have to water your plant during sunrise and sunset.
In a hydroponic system, ensure you give enough water and nutrients to keep the roots moist at all times without soaking them or drying them out.
- Ensure Proper Drainage

If your pots lack adequate drainage, the water may pool up and drown the roots.
On the other hand, if the drainage is too quick, the roots may not get enough time to soak all the nutrients from the water, leading to nutrient deficiencies.
Ensure the container has enough drainage to let around 20% of the water out quickly while preventing water pools within the substrate. You can also add other soil mixes like perlite or coco coir, or coco peat to retain water without drowning the roots. Avoid clay because it can hold too much water.
- Prevent Light Leaks

One of the worst root problems you can encounter is root rot, where fungi grow on the roots, locking other nutrients out. This usually happens when the roots are exposed to light. So, always keep the roots in darkness. Even a slight light leak can lead to fungi breeding on the roots, which can turn into root rot quickly.
- Give the Right Nutrients

The two essential nutrients (apart from nitrogen) for a healthy root ball are potassium and phosphorus, which strengthen the roots and encourage new growth. So, add some potassium and phosphorus mix into the substrate even before transplanting the seedling to give the roots a head start.
You can also add bone meal, wood ashes, kelp, or rock phosphate-rich fertilizers — into the substrate.
You should also give nutrients as per your plant’s growth stage since cannabis requires different nutrient concentrations during different growth stages. For example, use bloom-specific nutrients only during the flowering stage of the plant.
Otherwise, the roots may only consume some nutrients while leaving out the rest, creating a nutrient imbalance in the substrate.
- Balance the pH

Lastly, ensure the root zone has the right pH at all times. Cannabis prefers a slightly acidic environment with a pH between 5.5 to 6.5. If the pH of the substrate is too acidic or alkaline, it can cause various problems like a nutrient lockout, deficiencies, stunted growth, etc.
The right pH balance is crucial because the roots’ ability to absorb nutrients relies on the substrate’s pH. If the pH is off, roots fail to absorb some nutrients properly.
Invest in a pH pen to monitor the substrate pH regularly — for this, test the pH of the nutrient solution and the runoff water and compare the results — and use pH-up or pH-down solutions to re balance the pH if needed.
Summary
Keeping your plant’s roots healthy is the key to a healthy plant. The techniques mentioned above can help you do just that.
Right from the kind of seed you purchase and the container size to the pH and temperature — everything comes together to help the roots thrive.
If the leaves are your window into your plant’s health, healthy roots are the doorway to healthy plant growth. Never ignore the roots.