The 7 Cannabis Growth Stages

Cannabis, also known as marijuana or weed, is a fascinating plant that undergoes several distinct growth stages on its journey from a tiny seed to a mature flowering plant. Understanding weed growth stages is crucial for successful cannabis cultivation. In this article, we will explore the week by week stages of cannabis plant growth, from seed germination to harvesting a finished flower. It’s important to note that while there is a general timeline for each stage, the actual duration may vary depending on the strain of cannabis being grown. For instance autoflowering strains can finish in as little as 70 days from seed to harvest. And photoperiod strains like Lemongrass require 50 days, while Mountaintop Mint needs 70 days of flowering time. 

Lemongrass Autoflower cannabis seeds

Germination: The Journey Begins

The first stage of cannabis growth is germination. During this phase, the seed absorbs moisture and sprouts, developing a taproot that anchors it into the growing medium. The germination stage typically occurs within 24 to 72 hours after the seed is exposed to the right conditions, such as moisture, warmth, and darkness. Seeds require a warm, humid environment to sprout successfully. Some cultivators prefer using methods like the paper towel germination technique or direct sowing into the growing medium to initiate germination. Once the seedling emerges, it enters the next stage of growth.

Cannabis seedling poping out of seed germination

Seedling: The Emergence of Life

During the second phase of growth, the cannabis plant starts to develop its first set of leaves, known as cotyledons. These initial leaves are not “true leaves” and will have rounded edges and will provide energy to the young plant until it can start efficiently producing its own through photosynthesis. As the 2 week old seedling grows, it develops more leaves with the characteristic jagged edges associated with cannabis. The seedling stage of cannabis growth typically lasts for about two to three weeks.

During this stage, it is crucial to provide a stable grow environment with adequate lighting and nutrient light soil. If you start your seedling outdoors the natural sunlight will be the perfect lighting schedule. And if you start your seedling indoors a typical light cycle varies from 16 hours – 24 hours of light and 8 – 0 hours of darkness.

How to Germinate Cannabis Seeds

If you plan on moving your plants outdoors, it’s best to keep them as close to the natural light cycle as possible, this prevents triggering pre-mature flowering.

Seedlings are particularly delicate and should be handled with care to avoid damaging their fragile root system. Inoculating them with mycorrhizal fungi will help develop a stronger and healthier root system. This will result in more vigor, ultimately resulting in increased immunity to pests and heavier yield.

Vegetative: A Time for Growth 

The vegetative stage is where the cannabis plant experiences rapid growth and focuses on developing a robust structure. During this phase, the plant produces more leaves, and its branches become stronger and longer.

Vegetation stage is characterized by the plant’s intense green color and vigorous growth. Cultivators aim to create an optimal environment with proper lighting, temperature, humidity, and nutrient levels to maximize growth during this stage. 

Young cannabis plant growing in pot fan leaves

During this time your plant will be consuming larger quantities of nitrogen. You can provide your soil medium with neem or alfalfa meal or a balanced all-purpose fertilizer. You can supplement it with nitrogen rich nutrient solutions like those containing fish. If you’re feeling resourceful you can make your own DIY fish emulsion.

You can feed your plant with a nutrient solution once a week to ensure it receives adequate nutrition during this explosive growth phase. This period can last for several weeks to several months, depending on the strain and desired plant size.

Pre-Flowering: Reach for the Sky

The pre-flowering stage, also known as the stretch, occurs when the plant transitions from the vegetative stage to the flowering stage. It is characterized by a significant increase in vertical growth as the plant stretches to prepare for the upcoming flowering phase.

During this stage, the internodal spacing between branches increases, and the plant can double or even triple in size. It is essential to ensure that the plants receive sufficient vertical space and light coverage to prevent overcrowding and light deprivation.

This stage typically lasts 2-3 weeks and is when you will begin to see defined flower nodes where bud development will occur. These will be characterized by white hairs called pistils. It is important to keep your plant happy and healthy during this time and resist pruning it and disturbing the plant hormones that are accumulating in different parts of the plant.  

Flowering: The Beauty Blooms

The flowering stage is perhaps the most anticipated phase of cannabis growth, as it is during this period that the plant produces the resinous buds, we all know and love. The transition to the flowering stage is triggered by a change in light cycle, with most cultivators switching to a 12 hours of light/12 hours of darkness cycle. While the natural light cycle slowly decreases outside as your plant and growing season fades.

Cannabis plant flowering stage live cola close

Female cannabis plants begin to develop clusters of flowers known as buds, while male plants produce pollen sacs. It is crucial to identify male or female plants, and remove male plants to prevent pollination and seed development, unless specifically breeding for cannabis seeds. The flowering stage typically lasts for 7 to 14 weeks, depending on the strain. Indica varieties will have shorter flowering cycles compared to Sativa strains.


Once the marijuana plant has completed its flowering stage, it is time for harvesting. Harvesting involves carefully removing the mature buds from the plant. The optimal time for harvesting depends on various factors, such as the desired potency, aroma, and visual appearance of the buds.

Freshly harvested cannabis plant on an outdoor farm with a cat

 One common method of determining harvest readiness is to examine the trichomes, tiny mushroom-shaped structures on the buds, using a magnifying tool. When the trichomes turn from clear to a milky white and amber color, it indicates that the buds have reached their peak potency.

To harvest, carefully cut the branches with buds, leaving a bit of stem attached. Some growers prefer to perform a wet trim, removing the fan leaves immediately after harvest, while others prefer a dry trim, waiting until after the drying process. However you trim, it is best to work in cool temperatures to preserve the flavor and terpenes within your buds.

Post-Harvesting: Drying and Curing for Perfection

Once the buds are harvested, they need to go through the drying and curing process to develop their full aroma, flavor, and smoothness. Drying involves hanging the trimmed branches upside down in a dark, well-ventilated space with a moderate temperature (below 70F) and humidity(60% – 40% relative humidity). The goal is to slowly remove moisture from the buds without over drying them. This process typically takes about 7 to 10 days.

 After drying, the buds are ready for the curing stage. Curing involves storing the dried buds in glass jars or airtight containers, opening them periodically to release built-up moisture and allow for proper airflow. This process allows the remaining moisture to distribute evenly throughout the buds, resulting in a smoother smoke and enhanced flavors. Curing typically takes several weeks to a few months, with the buds improving in quality over time.

Frequently asked questions

How big should my plants be after two weeks?

The size of the plants after two weeks can vary depending on the strain and growing conditions. On average, you can expect the plants to have developed a few sets of true leaves and be a few inches tall.

How big should my plants be after four weeks?

After four weeks, the plants should have continued to grow and develop more leaves and branches. They can range in height from 6 to 12 inches, depending on the strain and growth conditions.

How big should my plants be after six weeks?

By six weeks, the plants should have significantly increased in size and foliage. They can range in height from 12 to 24 inches, again depending on the strain and cultivation practices.


Understanding the various stages of a weed plant is essential for successful cultivation. From seed germination to the flowering stage and harvesting, each phase has its unique requirements and characteristics. By providing the right environment, nutrients, and care, cultivators can nurture their cannabis plants through each stage and ultimately achieve a bountiful harvest of high-quality big buds. Whether you’re a beginner or an experienced grower, observing and tending to the growth stages of cannabis is a truly rewarding and exciting journey.