Understanding the Three Different Growth Stages of Successful Cannabis Grow​

1. Seedling Stage, 2. Vegetative Stage, and 3. Flowering Stage

Seedling Stage

Germination: The seedling stage begins with germination, where the cannabis seed sprouts and develops a taproot. This process typically takes 24 to 72 hours. After germination, the seedling emerges from the growing medium.

Cotyledon Development

Cotyledon Development: The first leaves to appear are the cotyledons, which are round and typically don't resemble the plant's typical leaves. They provide energy to the young plant until true leaves develop.

True Leaf Development

Once the cotyledons have fully developed, the plant starts growing its first set of true leaves. These leaves have the characteristic shape of cannabis leaves and are responsible for photosynthesis.

Light and
Nutrient Needs

Seedlings require a gentle light source, such as fluorescent lights or LEDs, positioned close to prevent stretching. Provide a mild nutrient solution formulated for seedlings. Avoid overwatering and ensure the growing medium remains moist but not waterlogged.


Seedlings can be transplanted into larger pots or the final growing location once they have developed a healthy root system. Handle the delicate seedlings with care to avoid damaging the roots.

Vegetative Stage

The vegetative light cycle of cannabis is when plant growth truly takes off. Much like a human adolescent, the plant will achieve most of its vertical growth during this time. Lasting between 3 to 16 weeks, the vegetative stage requires full-spectrum light for 18 hours and 6 hours of darkness.

Growth and Foliage Development

During the vegetative stage, the focus is on developing a strong root system, robust stems, and healthy foliage. The plant's primary objective is to grow in size and establish a strong structure. Leaf growth becomes vigorous, and the plant's overall height and width increase.

Light and
Nutrient Needs

Provide ample light during the vegetative stage, typically 18 to 24 hours of light per day. High-intensity lights, such as HPS or MH lamps, or LEDs are commonly used. Adjust the distance between the light source and the canopy as the plant grows. Use a balanced nutrient solution rich in nitrogen (N) to support vegetative growth.


This stage is ideal for implementing training techniques to control plant height, promote bushier growth, and create an even canopy. Techniques such as topping, pruning, and Low-Stress Training (LST) can be employed to encourage lateral branching and maximize light penetration.

Transplanting and Nutrient Adjustment

If necessary, transplant the plant into larger containers during the vegetative stage to accommodate its growing size. Adjust nutrient formulations to promote healthy vegetative growth and prevent nutrient deficiencies or excesses.

Flowering Stage

The cannabis flowering stage is when your plant switches from vegetative growth to producing bud. Outdoors it is triggered as daylight hours decrease, indoors it is triggered by changing to a 12/12 light cycle. It’s a crucial stage because the buds are the part of the plant that is rich in cannabinoids like THC.


As the plant matures, it will begin to show pre-flowers, indicating its sex. Male plants produce pollen sacs, while female plants develop pistils. Identify and remove any male plants to prevent pollination if growing feminized seeds or seeking seedless buds (sinsemilla).

Flowering Initiation

Once the plant receives 12 hours of uninterrupted darkness and 12 hours of light per day (12/12 light cycle), it triggers the flowering stage. The plant redirects its energy towards flower production. It is important to maintain a consistent light schedule to prevent light interruptions during the dark period.

Flower Development

During the flowering stage, buds start forming and gradually increase in size. Trichome production intensifies, and resin glands develop, containing cannabinoids and terpenes. The plant's height growth slows down, and the focus shifts to bud development.

Light and
Nutrient Needs

Adjust the light spectrum to emphasize red and orange wavelengths, as they are beneficial for flower development. Use bloom-specific nutrient formulations with a reduced.

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