It makes sense that creating a thick and healthy root mass helps produce high cannabis yields, but how to develop and maintain substantial root mass is the real challenge. In fact, there are many factors that must be considered, all of which are important to developing a healthy root zone for your plants to thrive.

First, think of the roots of your plant as if they’re the vital organs in your body. They need oxygen and a balance of certain nutrients to function. If the roots are not properly cared for, they won’t work to their full potential and your plant will likely suffer or die.

Let’s break down what you need to know about creating a healthy root mass for a successful harvest.

The Healthy Root Mass Equation

Cultivation is both an art and a science. You can’t just set containers out under a grow light, water your plants every couple of days and expect a robust harvest.

The equation for superior fruit mass is more complex, requiring you to keep a close eye on your plants to avoid issues like root stress, which can weaken a plant’s immune system and natural defenses. This increases the odds of potential problems in your growroom that will lead to reduced yields.

Start with the Right Container Size

In relation to plant size, container size plays a significant role in root health. When your pot is over-sized for a young or small plant, it increases the risk of over-watering, deprives the roots of oxygen, and increases the possibility of problems like disease and pests.

On the other hand, a small container with a large plant will result in your plant becoming root bound. This will cause your plants to have problems with water retention and nutrient uptake, which in turn will starve your plant.

Feed Your Plant the Right Nutrients

The main minerals associated with root growth and development are phosphorus and potassium. They promote the creation of new roots and strengthen existing ones as they mature.

Of course, oxygen is also required for cellular respiration and for roots to survive. Without proper amounts of oxygen, the roots will suffocate and weaken, potentially creating other problems. Low oxygen at the roots will reduce yields, quality, and can even result in your cannabis plant dying.

Proper pH is another essential part of the equation. With the correct pH balance, it will be easier for a plant’s roots to absorb the nutrients you provide. On the flipside, an improper pH balance can lead to the buildup of mineral salts in your medium, creating inefficient nutrient absorption and affecting plant metabolism. For cannabis plants, the recommended pH range is 5.5-6.5 for hydroponic applications and 6.0-7.0 for soil.

Adding beneficial bacteria, such as mycorrhizae, to your medium can boost root development, reduce transplant shock and allow roots to absorb nutrients at a quicker and more efficient pace. This fungus establishes a symbiotic relationship with plant roots, helping break down elements into a form plants can more easily use. It will also increase salt tolerance when feeding with an inorganic, salt-based fertilizer.

Keep in mind that germinated cannabis seeds and clones are fragile and susceptible to over-fertilization, especially during their early stages of life. Too many minerals will typically result in damage to the roots called root burn, which drastically slows or stops root development. You will want to focus more on aeration which can be increased through soil amendments to create better drainage.

Find the Right Balance for Watering

For novice growers, overwatering is a common problem. And it’s not just about the amount of water a plant is given — but the frequency and the ability for the plant’s roots to uptake the nutrients.

During the vegetative phase and the early stage of flowering, your plant is developing roots. As the medium starts to dry, the plant will search for water. This triggers root growth, which is essential for healthy plants. Allowing the medium to dry will help prevent root rot, one of the most common problems faced when growing cannabis indoors. However, avoid underwatering. During the mid- to late-flowering phase, underwatering can damage the plant, as well as reduce your yield and quality.

Then again, overwatering weakens a plant’s natural defenses and drastically increases the potential for pathogens or pests, such as fungus gnats and root aphids, to attack your roots. In time, you’ll learn how to find the balance between too much or too little water — it just takes practice.

Finally, let’s talk about water temperature. While often overlooked, it can affect water’s ability to retain oxygen molecules. Temperatures above 75°F drastically reduce the ability of water to retain oxygen. This creates an anaerobic condition that will very quickly degrade plant health and affect yields.

Using water that’s too cold can shock the plant, causing wilting and slowed or halted growth. The ideal temperature of your nutrient mix is 68- 70°F.

While growing your own cannabis might seem a bit daunting at first, focusing on root health is a great place to start. And by using the criteria outlined here, you’ll be well on your way. Remember to keep your grow area clean by removing sick or weak plants that can spread pests or other pathogens. Love your plants! It will help you achieve the high-yield harvests that you desire.

Good luck and happy growing!