It is possible to grow a plant from a seed found inside cured cannabis flower, commonly called “bag seed.” The presence of these seeds, often discovered accidentally, means the female flower was pollinated before harvest. While commercial cannabis is typically grown to be seedless (sinsemilla), finding a seed presents an opportunity for the home grower to cultivate a new plant.
Seed Formation and Viability
Seeds found within finished flower buds result from pollination, which initiates seed development within the female cannabis plant’s ovules. This process suggests the original growing environment was not perfectly controlled. Pollination occurs in two primary ways: external pollination, where wind carries pollen from a separate male plant onto the female pistils, or self-pollination.
The second, more common scenario for bag seeds, is hermaphroditism, where the female plant pollinates itself. Female plants develop male reproductive organs (often called “bananas” or “pollen sacs”) when they experience significant environmental stress, such as light leaks, nutrient deficiencies, or extreme temperature fluctuations. These structures produce pollen that fertilizes the surrounding female flowers on the same plant.
For viability, the resulting seed must spend four to six weeks maturing inside the flower. This period allows the seed to develop a hard outer shell and the necessary internal structures for germination. If a seed is fully formed and mature, it has a good chance of sprouting.
Assessing Seed Quality and Maturity
Before attempting germination, inspect the seed visually and physically to gauge its maturity. A high-quality, mature cannabis seed should have a hard, protective outer shell that cannot be crushed easily between your fingers.
Coloration is a strong indicator of maturity; viable seeds typically display dark brown, gray, or black shades. Many mature seeds also feature distinct patterns, such as mottled spots or “tiger stripes,” signifying full development. Conversely, pale green or white seeds, or those with a soft, easily cracked shell, are likely immature and have a low chance of germinating.
A simple inspection method is the buoyancy test. Place the seed in a glass of water for a few hours; viable seeds, due to their density, will typically sink to the bottom after one to two hours. Seeds that continue to float are often hollow or compromised, suggesting they may not sprout.
Understanding the Genetic Outcome
The most significant consideration when growing a bag seed is the uncertainty of its genetic makeup and gender potential. If the seed resulted from external pollination by a separate male plant, the offspring has an equal chance of being male or female. However, most bag seeds result from self-pollination by a hermaphroditic female plant.
Seeds produced by a stressed female plant are genetically female, meaning the resulting plant will almost certainly grow flowers. This creates an unplanned, naturally “feminized” seed. The drawback is that these seeds inherit the parent plant’s genetic predisposition to develop male flowers under stress.
The resulting plant will be highly susceptible to developing male organs, or “herming,” if it encounters similar stressors like light cycle interruptions, extreme temperatures, or nutrient issues. Careful monitoring is necessary throughout the plant’s life cycle, especially during the flowering stage, to remove any pollen sacs before they can pollinate the flowers. While there is a high chance of a female plant, it comes with an increased risk of instability compared to seeds bred for stability.
Initial Steps for Germination
Once a mature, viable seed is identified, the goal is to break its dormancy by providing warmth, moisture, and darkness. The paper towel method is a popular and effective way to initiate this process, allowing for easy monitoring. Place the seed between two lightly dampened paper towels, then seal them inside two plates or a plastic bag to retain humidity.
The paper should be wet but not dripping, as excessive water can cause the seed to rot. The ideal temperature for germination is consistently between 72°F and 80°F (22°C to 27°C). Placing the setup in a warm, dark location, such as a cupboard or on a seedling heat mat, helps maintain this optimal range.
Check the seed every 12 to 24 hours to ensure the paper towels remain moist and to look for the emergence of the taproot. Germination can occur in as little as 36 to 48 hours, though some seeds may take up to a week. Once the tiny white taproot extends to about 5 to 10 millimeters, the seed is ready to be gently transferred to its initial growing medium.