The Biology of the Cannabis Seed – Structure and Germination

The cannabis seed is the starting point of every cannabis plant and forms the basis for cultivation and propagation. Biologically, a cannabis seed is the fertilized seed of Cannabis sativa, containing all genetic information and the nutrient reserves required to develop a new plant.

1. Structure of the Cannabis Seed

A cannabis seed consists of several essential components that ensure its survival and its ability to germinate:

• Seed coat (Testa): The outer shell protects the sensitive embryo from physical damage, dehydration and pests. It is hard, smooth and often displays a characteristic marbled pattern.
• Embryo: Located inside the seed, the embryo is the precursor of the plant itself. It consists of:
  • Radicle: The first root that will develop into the main root system.
  • Hypocotyl: The lower part of the stem that connects the root to the young sprout.
  • Cotyledons: Two thick, rounded seed leaves that emerge first and supply the young plant with energy until photosynthesis begins.
• Endosperm: The nutrient tissue surrounding the embryo, storing starch, proteins and oils. These reserves supply the seedling until it can sustain itself through photosynthesis.

2. Germination of the Cannabis Seed

Germination begins when the seed is exposed to optimal environmental conditions. Three factors are crucial:

• Moisture: Water activates enzymes within the seed and softens the seed coat.
• Heat: Ideal temperatures range between 23°C and 25°C.
• Oxygen: Essential for cellular respiration and energy production in the developing plant.

Once the seed absorbs water, it swells and its metabolic processes activate. The radicle breaks through the shell first and forms the primary root. Soon after, the hypocotyl and the cotyledons begin to rise. Once the cotyledons reach the light, the plant initiates photosynthesis and becomes independent from the nutrients stored in the endosperm.

3. Influence of Storage and Seed Quality

The germination ability of a cannabis seed is strongly influenced by storage conditions. Excess humidity, temperature fluctuations or exposure to light can damage the delicate biological structures inside the seed and reduce germination rates. When stored correctly, cannabis seeds can remain viable for several years.

Genetics also play a major role: high-quality cannabis seeds come from stable parent plants that have been selectively bred for yield, resilience and cannabinoid profile.

4. Female vs. Male Seeds

Natural cannabis seeds randomly produce either male or female plants — a process still not fully understood and currently being researched. Learn more in the article “Increasing the Percentage of Female Plants in Regular Seeds.”

For flower production, only female plants are desired, as they produce the resin-rich buds. Therefore, many modern seed lines consist of feminized seeds, which produce almost exclusively female plants.

5. Seeds vs. Clones

Unlike clones (cuttings), which are genetically identical to the mother plant, plants grown from seeds show unique genetic variation. This can offer advantages (new, interesting traits) but also risks (instability).

In summary, the cannabis seed is a small but powerful biological unit containing life, energy and the full genetic potential of the cannabis plant. From germination to harvest, every grow begins with this remarkable natural structure.

Sex Determination in Cannabis – Genetics, Environment, and Hormonal Influence

There is strong evidence that the development of male or female cannabis plants is not purely random, but influenced by several internal and external factors. Sex determination in cannabis is complex and depends on both genetic predisposition and environmental conditions.

1. Genetic Predisposition

Each plant carries chromosomal information: Cannabis has X and Y chromosomes, similar to humans.

• Plants with XX chromosomes develop into female plants.
• Plants with XY chromosomes develop into male plants.

However, this genetic determination is not absolute, because…

2. Influence of Environmental Factors (Environmental Sex Determination)

Scientific studies and grower observations show that certain environmental conditions can influence the likelihood of a plant becoming male or female.

Key environmental factors include:

• Temperature: High temperatures tend to promote male plant development.
• Light intensity and spectrum: Stress caused by insufficient or excessive light can affect sex expression.
• Nutrient availability: Excess or deficiency of nutrients—especially nitrogen—can influence hormonal processes.
• Humidity: Very dry or overly humid environments can cause stress and influence sex development.

3. Plant Stress and Hermaphroditism

Under stress conditions (light leaks, nutrient problems, physical damage), some cannabis plants develop hermaphroditic traits: they produce both male and female flowers.

This mechanism is a survival strategy that allows the plant to self-pollinate when reproductive opportunities are limited.

4. Hormonal Regulation

The formation of male or female flowers is strongly influenced by plant hormones:

• Gibberellins promote the development of male flowers.
• Ethylen promotes the development of female flowers.

This is why hormones or chemical agents (such as colloidal silver) can be used intentionally to influence the plant’s sex—commonly used in the production of feminized seeds.

Conclusion

Sex determination in cannabis is not purely random but the result of an interplay between genetics and environmental factors. Growers can increase the likelihood of female plants by optimizing environmental conditions and avoiding stress. However, only feminized seeds offer a fully reliable outcome.

Indoor vs Outdoor Growing: Making the Right Choice

Choosing between indoor and outdoor cannabis cultivation is a key decision for every grower. Today, this choice is often influenced by the use of autoflowering cannabis seeds, which flower independently of the light cycle. Each growing method offers clear advantages depending on your goals, budget, and experience level.

1. Indoor Growing: Maximum Control & Simplicity

Indoor cultivation takes place in a fully controlled environment. Light, temperature, humidity, and nutrient supply can be precisely regulated.

Advantages of Indoor Growing

• Complete environmental control: Precise management of lighting (LED or HPS), climate, and CO₂ levels ensures consistently high quality.
• Year-round cultivation: Independent of seasons, 3 to 6 harvests per year are possible.

The Autoflower Advantage Indoors

Autoflowering cannabis seeds do not require a switch to a 12/12 light cycle. They can remain under 18–20 hours of light while flowering automatically. This significantly simplifies grow management. Their compact size also makes them ideal for small grow tents and discreet setups.

Disadvantages of Indoor Growing

• High costs: Significant electricity consumption and upfront investment in lighting, ventilation, and climate control systems.
• Limited space: Yield is restricted by the available grow area.

2. Outdoor Growing: Natural Efficiency & Flexibility

Outdoor cultivation harnesses the free power of the sun and natural conditions, but it is also exposed to environmental factors.

Advantages of Outdoor Growing

• Minimal costs: Sunlight is free, making outdoor growing highly economical and environmentally sustainable.
• High yield potential: Photoperiod plants can grow very large outdoors and produce kilogram-level harvests.

The Autoflower Advantage Outdoors

Autoflowering strains are true game changers outdoors. Because they do not rely on autumn light cycles, they allow multiple harvests per season, for example one in July and another in September. Their short stature (often under 1 meter) makes them much more discreet and easier to hide from unwanted attention.

Disadvantages of Outdoor Growing

• Weather risks: Frost, hail, or heavy rain can severely damage or destroy a crop.
• Pests & mold: Especially problematic during wet late-season conditions – a risk often avoided with autoflowers due to their early harvest.

3. Hybrid Growing: The Best of Both Worlds

Greenhouse cultivation combines indoor and outdoor advantages. Natural sunlight reduces costs, while the structure protects plants from harsh weather, pests, and temperature fluctuations.

When paired with autoflowering seeds, greenhouse growing becomes especially effective. Plants benefit from early spring sunlight, mature quickly, and remain protected from summer rain and high humidity.

Conclusion

Choose indoor growing if you want maximum control, top-tier quality, and year-round harvests. Opt for outdoor growing if your goal is to save costs and fully utilize natural resources. In both scenarios, autoflowering cannabis seeds are an excellent choice – particularly for beginners or growers seeking fast, easy, and discreet results.

Legal Status of Cannabis Seeds in Germany, Switzerland and Austria

The legal situation regarding cannabis seeds must be assessed differently in Germany, Switzerland and Austria, especially following recent legislative changes and clarifications of existing regulations. Although hemp seeds generally do not contain psychoactive substances and are therefore not classified as narcotics themselves, their legality often depends on the intended use and national cultivation laws.

Germany

With the entry into force of the Cannabis Act (CanG) on April 1, 2024, Germany implemented a fundamental shift in its drug policy. This has a direct impact on the legal status of cannabis seeds.

• Possession and purchase: The possession of cannabis seeds is legal for adults aged 18 and over. Purchasing seeds is also permitted. Adults may import or order cannabis seeds from EU member states for personal cultivation. Private individuals may order up to 200 cannabis seeds per year for personal use.
• Home cultivation: Adults are allowed to cultivate up to three female flowering cannabis plants at their residence or habitual place of stay for personal consumption. Excess plants or plant material must be destroyed immediately.
• Distribution: The distribution of cannabis seeds is strictly regulated. Cannabis Social Clubs may supply their members with up to seven seeds or five cuttings per month. Free commercial sale outside these associations is not permitted.
• Purpose limitation: Possession and cultivation are strictly limited to personal use. Commercial cultivation or trade remains illegal, except for licensed cultivation associations.
• Additional regulations: Plants must be protected from access by children and minors. Public consumption is prohibited in certain areas (e.g. near schools, daycare centers, playgrounds and sports facilities).

Overall, the legal situation for cannabis seeds in Germany has been significantly liberalized to allow private home cultivation.

Switzerland

In Switzerland, the legal assessment of cannabis is primarily based on the THC content.

• Possession and trade: The possession and trade of hemp seeds are generally legal, as the seeds themselves contain no THC and are therefore not covered by the Narcotics Act, unless they are clearly intended for the cultivation of high-THC cannabis.
• Cultivation: The cultivation of hemp plants is permitted as long as the THC content of the dried plant material remains below 1% (industrial hemp / CBD hemp). Cultivation of plants with 1% THC or more requires a special permit from the Federal Office of Public Health (FOPH).
• Import: Importing cannabis seeds is generally permitted. However, if there is clear evidence that the seeds are intended for the cultivation of THC-rich cannabis, this may be considered preparation for a narcotics offense.
• Practical application: In practice, purchasing cannabis seeds is usually unproblematic as long as there is no suspicion of illegal cultivation. Responsibility for lawful cultivation lies with the buyer.

As many international seed banks are unfamiliar with Swiss regulations, it is advisable for Swiss customers to purchase from specialized retailers who are experienced in compliant imports into Switzerland.

Austria

Austria takes a comparatively liberal approach to cannabis seeds and hemp cultivation, though important restrictions apply.

• Possession and trade: Possession and sale of cannabis seeds are legal. Seed banks may legally offer and ship seeds.
• Cultivation: Cultivation of hemp plants is permitted as long as the THC content of the harvested flowers does not exceed 0.3%, the legal threshold for industrial hemp.
• Intent: Cultivation becomes punishable only when there is an intention to produce a narcotic substance, such as harvesting THC-rich flowers. The mere existence of a cannabis plant is not automatically illegal.
• “Ornamental plants”: Many cannabis plants are sold as ornamental plants, as they often remain below the THC limit before flowering. Responsibility for further handling lies with the buyer.
• CBD flowers: The sale of cannabis flowers containing less than 0.3% THC (CBD flowers) is legal and widespread in Austria.

In summary, Austria allows the purchase and possession of cannabis seeds. However, the decisive factors are the THC content of the plant and the intent to produce narcotic substances.