The yield of four cannabis plants depends entirely on the grower’s environment and skill. Yield refers specifically to the final dry weight of the usable flower, and this measurement is highly variable due to several interconnected biological and environmental factors. A universal answer is impossible because everything from the strain’s genetics to the intensity of the light source influences the final biomass. This article explores the typical harvest ranges and the specific cultivation inputs that transform a small setup into a high-yielding operation.
The Estimated Yield Range for Four Plants
Controlled indoor cultivation and seasonal outdoor growth create the largest yield disparity for a four-plant setup. Indoor growers often measure success by the efficiency of their lighting, aiming for a benchmark of one gram of dried flower per watt of light used. Under a standard 600-watt fixture, a reasonable target for four plants is 600 grams total (about 21 ounces), averaging 150 grams (5.3 ounces) per plant. An inexperienced grower might achieve a low-end yield of 16 ounces total, while an expert maximizing a 600-watt light could push the collective yield closer to 30-40 ounces.
Outdoor cultivation offers the power of direct sunlight and nearly unlimited root space, allowing plants to grow significantly larger. A single outdoor plant grown in ideal conditions can easily produce 400 to 750 grams (14 to 26 ounces) of dry flower. This means a modest four-plant outdoor garden can yield a low estimate of 3.5 pounds (56 ounces) and potentially reach eight pounds (128 ounces) or more for experienced cultivators in long-season climates.
Key Cultivation Factors That Determine Output
The genetic makeup of the plants is the foundational determinant of their yield potential and physical structure. Indica-dominant strains tend to be short, bushy, and fast-flowering, making them ideal for indoor spaces with limited vertical clearance. Conversely, Sativa-dominant strains are tall and lanky with longer flowering cycles, meaning they are better suited for large outdoor gardens where they can reach their full potential height. Most modern, high-yielding options are hybrid strains, carefully bred to combine the best growth traits of both types.
Light intensity is the single most controllable factor driving flower density and final weight. Growers use Photosynthetic Photon Flux Density (PPFD) and Daily Light Integral (DLI) to measure the amount of light energy delivered to the canopy. Cannabis is a high-light crop, and dry flower yield increases linearly with DLI up to 50 moles per square meter per day (mol/m²/day) during the flowering stage. Delivering high light levels, often exceeding 1000 micromoles per square meter per second (μmol/m²/s) of PPFD, directly fuels the plant’s ability to create the dense sugars and oils that make up the final dry flower weight.
The choice of growing medium and the corresponding nutrient schedule significantly impacts the plant’s ability to absorb the necessary elements for growth. Hydroponic systems, which deliver nutrients directly to the roots in a water solution, can increase yields by 40 to 50 percent compared to traditional soil setups. Nutrient management focuses on tailoring the NPK (Nitrogen, Phosphorus, and Potassium) ratio to the plant’s specific growth stage. During the vegetative phase, a high-Nitrogen ratio (e.g., 3:1:2) supports the development of stems and leaves, while this ratio is flipped in the flowering phase to a high-Phosphorus mix (e.g., 1:3:2) to support the formation of dense buds.
Maintaining a stable atmosphere is achieved through precise environmental control, measured using Vapor Pressure Deficit (VPD). VPD quantifies the difference between the moisture inside the leaf and the moisture in the surrounding air, which dictates the plant’s rate of transpiration and nutrient uptake. During the vegetative period, a lower VPD of 0.8–1.2 kilopascals (kPa) promotes rapid growth, while the flowering stage requires a slightly higher VPD of 1.2–1.6 kPa to encourage water stress and denser bud production. This balance of temperature and humidity ensures the plant is always operating at peak efficiency.
Techniques for Maximizing the Harvest
Physical manipulation of the plant structure through training is necessary to fully capitalize on the ideal light and nutrient inputs. High Stress Training (HST), such as “topping” (removing the main growth tip), breaks the plant’s apical dominance. This disruption forces the redistribution of the growth hormone auxin, which encourages lateral growth and results in multiple primary flower sites, or colas, instead of a single main stalk. Low Stress Training (LST) involves gently bending and tying down branches to create a flat, even canopy, ensuring all potential bud sites receive an equal amount of light energy.
Canopy management techniques redirect the plant’s finite energy reserves to the most productive areas. Lollipopping is a technique that removes all the small branches and lower growth. By removing this lower foliage, the plant no longer wastes energy on producing small, airy “popcorn” buds, instead focusing resources on the top canopy that receives maximum light. Defoliation involves selectively removing large fan leaves that cast shadows, ensuring light penetrates deeper into the canopy and reaches secondary flower sites.
Harvest timing is determined by monitoring the microscopic resin glands called trichomes. These glands transition through three visual stages: clear, cloudy, and amber. Harvesting when the trichomes are predominantly clear is too early and can reduce the final dry weight by 20 to 30 percent because the buds have not fully swollen. Peak biomass and potency are achieved when the trichomes are mostly cloudy, indicating the highest concentration of psychoactive compounds; allowing them to turn amber signals the end of the dry weight gain window and results in more sedative elements.