Yield, defined as the dried, processed weight harvested per plant, is not a fixed number. It is dictated by a complex interplay of variables. There is no single average because the output potential is sensitive to the plant’s genetic code, the environment, and the specific cultivation techniques employed by the grower.
Establishing a Baseline Yield Range
The total yield from a single plant can vary drastically, ranging from less than one ounce to several pounds, depending primarily on the growing environment. Cultivation outdoors offers unlimited root space and the full spectrum of natural sunlight, often resulting in massive plants that can produce between 14 and 26 ounces (400 to 750 grams) on average. Under optimal conditions and with a full growing season, some large outdoor plants can exceed 35 ounces of dried material.
Indoor cultivation, by contrast, involves controlled environments where space and light are limited, leading to smaller, more manageable plants. A typical indoor harvest for a single plant generally falls between 7 and 14 ounces (200 to 400 grams) of dried material. Plants with a short life cycle, such as autoflowering varieties, usually produce less, averaging between 1 to 5 ounces (30 to 150 grams) per plant due to their smaller stature and compressed vegetative phase. Expert growers can push indoor yields higher, sometimes achieving up to 26 ounces per plant by maximizing every environmental and genetic factor.
The Influence of Genetics and Strain Type
A plant’s inherent biological blueprint establishes the maximum yield it can achieve, regardless of the grower’s skill. The genetic background dictates plant morphology, which strongly influences how much biomass a plant can generate. Cultivars with an Indica-dominant background typically exhibit a short, bushy structure with denser foliage and a shorter flowering time. This structure is associated with higher yields per plant mass, making these varieties popular choices for indoor spaces with limited vertical height.
Sativa-dominant cultivars, conversely, tend to grow tall and lanky with thin, narrow leaves and a much longer flowering cycle. While a large Sativa plant grown outdoors can produce a substantial harvest, they generally offer lower yields per plant in controlled indoor environments due to their vertical growth pattern and longer time to maturity. Most modern cultivars are hybrids, meaning they blend the traits of both types, allowing breeders to select for desirable characteristics like the dense bud structure of an Indica combined with the faster vegetative growth of a Sativa.
Optimizing Environmental Conditions
Environmental control represents the grower’s ability to maximize the genetic potential of the plant. Light intensity and duration are the primary drivers of biomass production, measured by Photosynthetic Photon Flux Density (PPFD) and Daily Light Integral (DLI). DLI is the total amount of photosynthetically active light received by the plant canopy over a 24-hour period, and is a better predictor of yield than simple light intensity alone.
For optimal flower development, the target DLI is typically 40 to 55 moles per square meter per day (mol/m²/day). This often corresponds to a PPFD of 600 to 900 micromoles per square meter per second (\(\mu\)mol/m²/s) during the 12-hour flowering cycle. Temperature and humidity must be precisely managed to maintain an optimal Vapor Pressure Deficit (VPD), which regulates the plant’s transpiration rate and nutrient uptake. An ideal VPD range of 0.8 to 1.2 kilopascals (kPa) promotes healthy water movement and nutrient transport.
In closed-loop indoor systems, high light levels exceeding 800 \(\mu\)mol/m²/s can be utilized by supplementing the air with carbon dioxide (\(\text{CO}_2\)). Ambient \(\text{CO}_2\) levels are around 420 parts per million (ppm), but plants can efficiently use light up to a DLI of 60 mol/m²/day when \(\text{CO}_2\) is enriched to levels between 1,000 and 1,500 ppm. This supplemental \(\text{CO}_2\) acts as a building block for photosynthesis, allowing the plant to process the increased light energy for enhanced growth and yield.
Cultivation Techniques for Maximizing Output
The final factor in yield is the active manipulation and skill of the cultivator, focusing on techniques that maximize the plant’s light exposure and nutrient efficiency. Training methods are designed to create a broad, flat canopy where all flowering sites receive uniform light intensity. Low Stress Training (LST) involves gently bending and securing branches to encourage horizontal growth, which directs energy to lower nodes and improves light penetration.
A common high-stress technique is topping, where the apical growth tip of the main stem is removed. This redirects growth hormones to the lateral branches, forcing the plant to develop multiple main flowering sites instead of one dominant central cola. The result is a bushier structure with more high-yielding zones.
The Screen of Green (SCROG) method uses a horizontal net to train branches, ensuring an even canopy where every potential bud site is positioned to receive maximum light. The choice of growing medium also impacts yield through its effect on nutrient delivery and growth rate. Hydroponic systems, which deliver a precise nutrient solution directly to the roots, often facilitate faster growth and higher yields compared to traditional soil. Regardless of the medium, careful management of macro- and micronutrients, along with maintaining the correct pH level, is necessary to ensure the plant can efficiently absorb the resources needed for maximum flower production.