Increasing Cannabis Yields: Understanding Light, Soil, and Growth

Increasing cannabis yields means gaining a better understanding of the interplay between genetics, light, climate, root space, soil life, plant structure, and harvest timing . Anyone planning a hemp project wants to end up with healthy, robust, and aromatic flowers. However, it’s not just about maximizing plant biomass; above all, it’s about consistent quality.

This article examines the topic from the perspective of plant biology and CBD hemp in Switzerland. In the Swiss context, hemp containing less than 1 percent THC is not classified as a narcotic. Nevertheless, the legal framework, product categories, and intended use remain important. Those looking for relevant information on hemp cultivation will find a good overview in our “CBD Cultivation in Switzerland” category. At the same time, this blog deliberately focuses on the question of which factors influence yield and plant quality.

In a nutshell: How can you increase your cannabis yield?

Increasing cannabis yield means optimizing growing conditions so that a plant can reach its genetic potential while remaining as healthy as possible. To do this, it needs sufficient light, adequate root space, stable temperatures, appropriate humidity, good growing medium, and a clean plant structure.

The key point, however, is this: Higher yields are rarely achieved through a single trick. Rather, a good harvest is the result of many small decisions. Those who focus solely on fertilizer but neglect light, climate, or root health are wasting potential. On the other hand, those who understand the basics can better manage growth, flowering, and quality.

Increasing Cannabis Yields Through Light and Photosynthesis

Light is one of the most important factors for growth and flowering. Through photosynthesis, plants convert light energy into biomass. In professional cultivation, terms such as PPFD and DLI are used for this purpose. PPFD describes how much usable light reaches a given area. DLI, in turn, describes the total amount of light a plant receives per day.

Studies on Cannabis sativa show that light intensity can affect photosynthesis, flower yield, and quality. However, this does not automatically mean that more light always leads to better results. The key factor is the balance between light, temperature, water, nutrients, and plant health. Too little light limits growth. Too much light without a stable climate, on the other hand, can cause stress.

In practice, this means that uniform illumination is often more important than individual peak values. Indoors, modern LED systems, the distance from the plant, and uniform light distribution therefore play a key role. Outdoors, however, location, hours of sunlight, shading, and weather protection determine how well a plant can reach its full potential.

Climate and VPD: Why Balance Is More Important Than Extreme Values

In addition to light, the climate also determines how efficiently a hemp plant can grow. Temperature and humidity should not be considered in isolation. The so-called VPD value—short for vapor pressure deficit—describes the relationship between humidity, temperature, and the plant’s water release.

Plants regulate their water balance through the stomata on their leaves. If the climate is too dry or too humid, the plant can close these stomata more tightly. This can affect transpiration, nutrient uptake, and photosynthesis.

If you want to increase your cannabis yield, you should therefore ensure stable conditions. Good air circulation, adequate humidity, appropriate temperatures, and a balanced water supply form the foundation for healthy plants. Extreme conditions are rarely the goal, because a healthy balance is more reliable in the long run.

Genetics as the foundation for healthy hemp plants

Genetics determine growth, structure, flowering, aroma, and hardiness. Some plants grow compactly, while others branch out more. Some strains produce large buds, while others stand out for their scent, resin content, or resilience.

That is why every yield strategy begins with the selection of the starting material. Healthy seedlings and stable genetics make planning easier. Those who work with cuttings often benefit from more uniform growth. Seeds, on the other hand, offer greater genetic diversity.

We discuss the fundamental question of whether seeds or cuttings are better in more detail in our blog post “Cannabis Seeds or Cuttings.” In this article, however, the focus remains on yield: a plant can only produce what its genetics and health allow.

Plan root space, pot size, and growing medium carefully

A large portion of the yield is produced underground. Roots absorb water and nutrients, stabilize the plant, and interact with the growing medium. Studies on pot size show that limited root space can restrict plant growth. At the same time, more space does not automatically lead to better results if the light, water, growing medium, or climate are not suitable.

A pot that is too small can restrict growth. However, a pot that is too large can lead to waterlogging and root problems if not watered properly. It is therefore essential to choose a pot size that is appropriate for the plant’s size, its location, and the amount of care it requires.

The growing medium is also crucial. Good soil retains water, remains well-aerated, and supports active soil life. Those who think long-term therefore focus not only on the immediate availability of nutrients, but also on soil structure, microorganisms, and root health.

Living Soil and Soil Life as a Factor in Crop Yield

Living soil, compost, microorganisms, and mycorrhizal fungi are becoming increasingly important in hemp cultivation. The basic idea is simple: a plant does not grow in isolation, but in connection with the soil, microorganisms, water, light, and its environment.

Mycorrhizal fungi can extend the effective reach of the root system and support nutrient uptake. Studies on cannabis are examining these fungal systems in relation to growth and cannabinoid yield. This highlights why healthy soils are important for plant quality and stability.

It’s important, however, to draw a clear distinction: This blog explains soil life as a factor in crop yield. You can find the specific story about sustainable Swiss cannabis cultivation, Herba di Berna, and Slow Weed in the article “CBD Cultivation: Herba di Berna and Slow Weed.” This article, therefore, remains focused on technical and plant biology aspects.

Shaping Plant Structure: Topping, LST, and Defoliation

Many methods for increasing yield focus on the plant’s architecture. By nature, cannabis often develops a dominant main stem. This principle is known as apical dominance. The main stem influences how vigorously the side shoots grow.

Techniques such as topping or low-stress training can help distribute light more evenly across multiple shoots. Topping involves removing the main growing tip. Low-stress training involves gently guiding the shoots to create a flatter plant structure. Defoliation and lollipopping, on the other hand, aim to reduce areas with low light and improve air circulation.

However, these methods do not guarantee higher yields. While they can be effective under the right conditions, they can also cause stress if used incorrectly. Therefore, training techniques should always be tailored to the plant’s genetics, the timing, the location, and the grower’s experience.

Increase cannabis yield without compromising quality

A higher yield only makes sense if the quality is right. With CBD flowers in particular, it’s not just weight and volume that matter, but also aroma, plant profile, resin content, drying, and processing. A heavy harvest is of little use if the flowers are harvested too early, dried poorly, or stored incorrectly.

Terpenes define the scent and strain profile of a cannabis plant. Anyone looking to maximize both yield and quality should therefore pay close attention to ripeness, gentle processing, and proper storage. You can find more information about scent, aroma, and strain profiles in the blog post “Cannabis Terpenes Explained.”

The timing of the harvest is also crucial. You can find a detailed overview of this in our article on harvesting cannabis. This article focuses specifically on increasing yield and refers readers to the relevant special article for information on the harvest phase.

Compatible attachments for better control

If you want to increase your cannabis yield, you don’t necessarily need complicated equipment. Often, simple tools are enough to help you better control your plants and care for them more effectively. These include, for example, measuring devices, growing accessories, planters, pruning shears, storage solutions, or products for a neat grow setup.

In our ” CBD Cultivation in Switzerland ” category, you’ll find practical guides on all things hemp, including care and processing. The focus here isn’t on breaking artificial records, but on clean work, thorough preparation, and a deeper understanding of the plant.

If you prefer premium Swiss quality, our CBD flowers offer carefully selected products made from legal hemp. Herba di Berna is based in Bern and delivers quickly throughout Switzerland, from local specialty shops to every canton.

Conclusion: Increasing cannabis yields starts with understanding the plants

There is no single method for increasing cannabis yields. Vigorous plants result from the interplay of genetics, light, climate, root space, soil life, plant structure, and harvest timing. Understanding these factors allows you to better assess growth and quality.

This blog is intended to complement our existing content, not replace it. Our Slow Weed blog explains sustainable Swiss cultivation practices. Our Cuttings blog helps you get started. Our Harvest blog covers the right timing. This post, on the other hand, focuses on the question of which plant-biological factors influence yield.

If you’re planning your own hemp project, you’ll find the basics you need in the ” CBD Cultivation in Switzerland ” section, along with more detailed information in our blog posts on soil, terpenes, and harvesting.

List of sources & references

• BLW: Hemp in Switzerland Information on hemp, THC limits, and the legal status of hemp in Switzerland. Source
• Rodriguez-Morrison et al.: Cannabis Yield, Potency, and Leaf Photosynthesis —A study on light intensity, photosynthesis, yield, and quality in Cannabis sativa. Source
• Grossiord et al.: Plant Responses to Rising Vapor Pressure Deficit. A review of VPD, stomata, transpiration, and plant growth. Source
• Poorter et al.: Pot size matters: A meta-analysis of the influence of pot size and root volume on plant growth and biomass. Source
• Seemakram et al.: Arbuscular mycorrhizal fungi and Cannabis sativa. Study on mycorrhizal fungi, growth, and cannabinoid yield in Cannabis sativa. Source
• Kebrom: A growing stem inhibits bud outgrowth Research article on apical dominance, shoot development, and plant architecture. Source