Cannabis growth stages breakdown (2024)

Growing cannabis can seem easier when the process is broken down into the 4 main cannabis growth stages. These are the cannabis seed germination, seedling, veg and bloom. At each stage the requirements for nutrients, light and water will vary. The experienced cannabis grower will know how to give the right environmental conditions at each of the stages of cannabis growth. However cannabis plants will always teach you something new to improve the way you grow. Dive into this guide to learn all you should know about the life cycle of cannabis!

How long is a cannabis full grow cycle on average?

There are 4 main stages of the cannabis life cycle as it transitions from seed to harvest. Germination is often defined as the time taken from planting the cannabis seed to the point where it has produced it’s first cotyledon leaf pair. These are the first ‘baby’ (non-serrated) leaf set which is formed as the seed germinates.

The cannabis plant life cycle for a fast growing autoflower seed variety such as as Auto Blueberry or Auto Blackberry Kush could be as little as 9 weeks from seed to harvest.

Or it could be a 6 months cannabis life cycle for an outdoor seed variety. The indoor cannabis grower has full control over their plants and the environment. This allows indoor feminised seed growers to dictate the length of vegetative growth, which in turn will affect final plant size, yield and overall life cycle.

The length of the cannabis full grow cycle will depend on your choice of cannabis seeds (autoflower seeds vs feminised seeds) and whether you grow them indoors or outdoors.

Cannabis germination stage (2-10 days)

Cannabis seeds are typically small, hard and dry. The colours vary from light to dark brown. The first cannabis plant stages take place after the seed has germinated. During seed germination the shell of the seed is initially softened by the moist germination conditions. It’s important to provide moist, but never soaked, conditions for cannabis seed germination in order to achieve maximum germination rates from your precious seeds.

Cannabis seeds should be germinated in dark conditions and don't need any nutrients initially. Water is sufficient for the first few days. The tap root will emerge from the cannabis seed and grow downwards. The first set of cotyledon leaves will emerge and the cannabis grow cycle has begun! Note that these leaves don't have the ‘normal’ serrated edges which you will see on all subsequent leaves. As all this is happening the cannabis root system starts to form.

It can take around 2-10 days for seed germination to occur. Occasionally, cannabis seeds can take up to 2 weeks to germinate. Eventually you will see the first set of ‘true’ cannabis leaves with serrated edges appear. For many growers, this represents the end of the cannabis germination stage and the start of the seedling stage.

How long does it take to germinate cannabis seeds?

It can vary from one cannabis seed to another. Usually you can expect seeds to germinate somewhere around 2-10 days after you begin the germination process. Occasionally you can get cannabis seeds to germinate in just one day. Sometimes it can take around 2 weeks. But usually you can expect to wait around 2-10 days for your cannabis seeds to germinate.

Can you speed up the germination process?

Not really. You need to provide good cannabis seed germination conditions and then wait for nature to do her work. If you have bought good quality cannabis seeds from a proven supplier than you can expect cannabis seed germination rates of 90%+.

Many growers have accidentally killed their plants during germination by trying to speed things up by a day or two. It definitely isn't recommended to e.g. sand-paper your seeds to reduce the shell thickness in an attempt to speed up germination. Nor is it recommended to try to force the shell off the plant during germination. Instead, just be patient and allow the cannabis genetics to do their work.

When to transplant cannabis seedlings?

If you have germinated your cannabis seeds with the moist cotton pad method then you will simply place the germinated seedlings in your grow medium (e.g. soil or coco fibre) or your grow system (e.g. DWC or NFT hydroponic system).

Many growers that use e.g. autoflowering cannabis seeds will simply put their seedling into the final grow container. This avoids the need to repeatedly transplant the seedling to progressively larger containers. In the case of an autoflower strain with a limited lifetime, this process allows the auto to focus all the available time on growth. No plant time is spent adapting during repeated transplants, allowing your auto to reach maximum potential.

Those that grow photoperiod feminised seeds indoors can choose when the blooming process starts simply by reducing daylight hours. That gives them more time to spend progressively potting up and transplanting into gradually larger containers if they wish.

Cannabis seedling stage (2-3 weeks)

For the next 2-3 weeks after germination, the cannabis seedling will grow. The cannabis root system is essential for healthy growth and development. Experienced growers aim to deliver fully optimised grow conditions in order to maximise root growth. Give the roots waterlogged cold soil and they won't grow well, this may result in a permanently stunted plant.

Above ground, the cannabis seedling will continue to grow. With each new set of leaves you may notice progressively more ‘blades’ or fingers on the leaves. Initially you may see 3 fingers, then 5 or 7 etc. During the life cycle of cannabis, the seedling needs less water and nutrition than it does in subsequent veg growth and flowering stages. This is one of the most delicate cannabis growing stages. The seedling needs little water and minimal nutrients.

If growing in light mix soil there you may not need to consider any grow nutrients until a week after the first set of serrated leaves emerge. Generally, a light mix soil has enough nutrition for the first couple of weeks after cannabis seed germination. After that many growers use root stimulator and grow nutrients.

If you are growing in hydroponics or coco fibre you may already be carefully using very light nutrients on young seedlings. You may prefer to use specialist low strength seedling nutrients at this stage. The goal is to keep the cannabis seedling in the nutrient sweet spot without over feeding or underfeeding. If seedlings are given excessive nutrients it can ‘burn’ the plant, permanently limiting future growth.

How long does the cannabis seedling stage last?

Many growers consider the first 2-3 weeks after germination to be the cannabis seedling stage. These are the first couple of weeks where the seedling is most vulnerable. The seedling may only be a few inches/cm tall with a couple of sets of true (non-cotyledon) leaves.

Lighting levels don't need to be particularly intense for cannabis seedlings, for the technically minded PPFD levels of 200-400 should be adequate. Many use T5 fluorescent tubes for cannabis seedling lighting. The delicate young seedling leaf tissue can be damaged by the intense light levels which you will need in later cannabis flowering stages.

If you do see your cannabis seedlings stretching a little too much it can help to reduce the distance between the plants and the light. With higher light intensities, the stretching should reduce. If your seedling suffer elongated stems you can gently prop up your seedling with some small wooden supports, such as toothpicks (or similar)

What does a healthy cannabis seedling look like?

You can expect a short, squat plant. The cotyledon leaves will be small in comparison to the emerging ‘true’ leaves and you will notice new leaf sets emerging from the central growing point of your plant (the ‘apex’). The colour should be a vibrant green. Any signs of yellowing is a signal that something is wrong. If your seedling has brown leaf tips it’s a sign that you have overfed your seedlings and ‘burned’ the plant. This is never a good sign and can temporarily or permanently restrict future growth.

If you have a healthy cannabis seedling it will have all the basics in place for future growth. The roots should have the space and nutrients/minerals required to grow a larger frame. The leaves will be ready to grow and absorb more light which will power future photosynthesis. Your plant is set for vegetative growth and will be ready for more light, nutrients and water.

Autoflower seed growers may already have their plant in the final grow container at this stage.

Cannabis vegetative stage (3-15 weeks)

Vegetative growth is the indoor cannabis growing stage where roots, branches and leaves grow but no buds are formed. Indoor growers often use 18-24 hours of daily light whether they are using autoflower seeds or photoperiod feminised cannabis seeds.

During vegetative growth the cannabis plants gradually grow in both height and width. Nitrogen rich nutrients are particularly useful in the vegetative growth stage. The first sets of cannabis leaves grow gradually larger and new leaf sets are formed. As the plant grows it’s requirements for nutrients, water and light will all increase. Light levels can be increased from around 200 PPFD to nearer 400-600 PPFD - your light manufacturer should be able to detail the PPFD levels at various hanging heights.

How long should a cannabis plant stay in veg?

Those growing photoperiod feminised cannabis seeds can select the length of the vegetative growth stage. Often it’s around 4-6 weeks for many growers. But some growers, e.g. SCROG growers (Screen Of Green method), prefer very long periods of ‘veg’ growth, in extreme cases up to 15 weeks or so. However, SOG growers (Sea Of Green method), may not give their plants any veg growth and instead put them straight into bloom conditions.

Those growing autoflower seeds will not be able to dictate the length of the vegetative growth phase. Instead the autoflower seed genetics will determine the point at which it automatically transitions from veg to bloom. It does this without any change or alteration to the light cycle. Autoflowering cannabis seeds grow from seed to harvest under the same light cycle, typically 20 hours of daily light. Photoperiod feminised cannabis strains only commence bloom when indoor light hours are reduced to 12 per day.

How does a healthy cannabis plant in veg look like?

Much depends on the length of time the plant has been in the vegetative growth stage for. A feminised strain with 15 weeks of veg growth could have filled a very large SCROG screen. Whereas an autoflower plant in veg may be perhaps 10-20cm tall, perhaps 3 weeks old and ready to start stretching once bloom begins. Much depends on your cannabis genetics and grow style. But you can expect to see a medium-sized plant with healthy green foliage, but no buds.

Why does my cannabis plant want to flower in the vegetative stage?

The cannabis flowering stage follows veg growth. Cannabis plants are genetically geared towards bloom. It’s the only chance for cannabis to produce seeds and produce the next generation of plants. You may see pre-flowers at the nodes between the stem and branches. Autoflower genetics don't hold back. As soon as they are ready, autos start to transition from veg to bloom. During this process the auto exhibits features of both veg and bloom.

Cannabis flowering stage (7-14 weeks)

During the cannabis flowering stages, the female plant produces buds and resin. The flowering stage follows the vegetative growth stage. When growing autoflowering cannabis seeds, the transition from the vegetative stage to the flowering stage happens automatically (hence the name, autoflowering).

When growing photoperiod feminised cannabis seeds, bloom begins indoors when the daily light hours are decreased to 12. Outdoors, feminised strains sense the shortened daylight hours as autumn/fall approaches and bloom begins. However if you are growing at equatorial regions the plants can sense the short days immediately.

During the cannabis flowering stage, the plant will require gradually increased levels of nutrients and water. Phosphorus will be required in greater quantities as the plant biochemistry changes. During the cannabis flowering stage the plant biomass can increase dramatically.

Intense light levels can be used in bloom, often with PPFD levels of 600-900. More light can deliver heavier yields. Some professional cannabis growers used PPFD levels of around/over 1000 and may also supplement with Carbon Dioxide to further boost yields.

The length of the flowering stage depends on the genetics. 7 weeks of bloom is required by fast flowering indica strains such as Bubba Island Kush seeds. But a slow blooming Haze may require upwards of 14 weeks in bloom.

The following cannabis flowering stages are shown in week by week pictures, below.

How to tell if a cannabis plant is ready to bloom?

Knowing when your plant is ready to be flipped from veg growth to bloom is one of the most important decisions you will make. But first you may wish to consider a few points related to the timing of the cannabis flowering stage.

• The height of your grow room may be a limiting factor. If you have restricted vertical growing space you may prefer to have minimal veg time.

• Are you growing indica or sativa cannabis seeds? Sativa strains may stretch dramatically during bloom. Take this into account when deciding if your cannabis plant is ready to bloom.

• Growing clones or seeds? Clones don't always have well established root systems and can take a while to create one before being flipped into bloom.

• Outdoor plants can also be forced into early bloom if you have a greenhouse equipped with blackout blinds. Otherwise, they will choose their own moment to bloom as daylight hours shorten.

• Which growing method are you using? If using the SCROG method you may wish to wait and give the plant a long veg stage. If using the SOG method you may want to offer minimal veg time or even none at all and grow from seed to harvest under 12/12 light

• Which region/climate are you growing in? If you’re growing in tropical equatorial regions you may want the most sativa dominant strains with the most stretch. That’s because the plants go into flowering more-or-less immediately. In more temperate climates, the plants commence bloom as daylight hours shorten. For Northern Hemisphere growers (Europe, USA etc) this often happens around August.

How long does it take for cannabis to start blooming after switching the light cycle?

Once you switch the light cycle to 12/12 (12 hours of daily light) the plant undergoes plant hormone changes as it senses the shorter days.

The plant hormones cause the plant to prepare for bloom. Over the following week or so you will see the changes on the cannabis plant as she gets ready to stretch and produce flowers. You may see female pre-flowers producing a couple of pistils (hairs) at the node between the stem and a branch.

However you can expect to wait 1-2 weeks before you start to see flowers starting to appear. With certain sativa and hybrid strains it can take 3-6 weeks before any significant flower formation.

How does a healthy cannabis plant in flowering look like?

Initially you may notice areas of light green foliage at the eventual points where buds will eventually form. You may also notice the plants stretching, with increased internodal distance.

Growers monitor their cannabis flowering stages week by week. Some like to consider the cannabis flowering stage as 3 separate mini-phases; early bloom, mid bloom and late bloom. As your cannabis plant flowers the weight of buds and resin should increase as harvest point approaches.

During the cannabis flowering stage you will notice that your plant appetite for nutrients reaches maximum as it produces bigger buds and more cannabinoid-containing resin. The ratio of required nutrients will change too. Less Nitrogen (N) is required and increasing amounts of Phosphorus (P) and Potassium (K) are needed to support heavy harvests of compact flowers.

During the first few weeks of bloom your plant will stretch. A sativa may stretch to 2-3 times the height it was at the end of veg. You will see increasing amounts of pistils being produced and the buds start to form and eventually fatten up. After around 5 weeks of bloom the cannabis plants have generally stopped stretching and the buds start to get larger.

As harvest approaches, the pistils start appearing as orange rather than white.

How to tell when your cannabis buds are ready for harvest?

Your cannabis seed supplier should give an indication of the approximate length of the flowering stage. This is a guideline rather than a fixed rule and it may indicate the typical earliest harvest point rather than the recommended harvest time.

Environmental conditions and the specific phenotype will determine the actual harvest date. In addition, you may have a preference for early, mid or late harvested buds.

There are various cannabis bud growth stages. They start small and gradually pack on weight and resin as they grow. Some growers like the slightly heavy effects (and more generous yields) offered by allowing the buds a week or two extra in bloom.

There are different cannabis trichomes stages to consider. Immature buds tend to have clear trichomes. As the buds approach harvest the trichomes become cloudy and eventually start to produce amber (or even red) colourations. Many harvest their buds as the trichomes are transitioning from clear to cloudy.

What to do in case of early or late flowering?

If your plant flowers early you can look forward to an earlier harvest. A late flowering plant will generally have enjoyed more time for veg growth, so you may be able to look forward to a heavier harvest.

When growing autoflower seeds you may find some plants will be ready to harvest a week or two before the slower phenotypes. Remember each plant is different. Try to time the harvest so that you have buds of the perfect maturity level for your personal tastes. Some growers love the lively energetic buzz from an early harvested plant. Other growers will always wait an extra couple of weeks to ensure that their plants have a high proportion of amber trichomes which can produce heavier effects.

What really matters to the home grower is that they:

• are growing the best cannabis seeds for them personal needs and,

• they select the optimised harvest date which provides maximum enjoyment and satisfaction for their recreational or medical needs.

Other important cannabis life cycle considerations

There are different cannabis growth stages as well as different cannabis flowering stages. The experienced grower understands the various environmental, nutrient and lighting requirements at the various stages of cannabis growth.

What stage of growth does cannabis produce trichomes?

This can depend on the specific cannabis seeds being grown. Trichomes can be seen even on young plants though they can be microscopically small. As the plant matures the amount of trichomes increases dramatically. When growing photoperiod feminised cannabis seeds you may see the first trichomes around 3 weeks into bloom. Over the following month trichome production is heavy and gives the plant a frosty appearance, as if sprinkled with sugar.

When growing autoflower seeds, trichome production tends to start around 4 weeks after germination. In the following weeks, trichome production steps up a gear as the buds gain weight. Aroma also increases as more and more trichomes are produced.

What stage of growth does cannabis stop growing?

During flowering, most photoperiod cannabis plants stop stretching after around 4-5 weeks. After that point most of the growth happens on the buds. For autoflower plants, stretch tends to stop around 6-7 weeks after germination. At that point the bulk of the plants energy is focussed on bud growth and resin production.

But it’s worth adding that these figures are only approximate. Much depends on the specific cannabis genetics that you are growing, your environmental conditions and the grow method.

How long should the harvested buds be left to dry?

Harvested buds are typically left for 7-14 days to dry before being transferred to the curing jars. When the branches ‘snap’ (rather than bend) it’s an indication that the plant is dry enough for curing to begin.

How long should the harvested buds be cured?

Many would say that a month or two is a realistic minimum to allow the taste and aromas to fully develop. Keeping your cured buds in jars even longer isn't an issue. Many people feel that a 6-month cure with your jars in cool/dark conditions is a great way to maximise taste and aroma.

How to keep a consistent cannabis growth timeline?

When growing photoperiod feminised cannabis seeds the growth timeline is up to you. You can offer minimal veg growth for a SOG grow or several months for a SCROG grow.

Autoflower seeds, on the other hand, have a cannabis growth timeline of their own. They, not you, decide when to start blooming. Good quality auto seed suppliers should be able to give you a good idea whether they are likely to have a growth lifecycle as fast as 9 weeks e.g. Auto Blueberry seeds or a slow growth lifecycle of 12-15 weeks e.g. Auto Ultimate seeds. Note that the autos which take longer to grow may well deliver very heavy yields.

Outdoor cannabis growers should note that the different regions you live in can also determine how many daylight hours per day you will have. That will have a huge influence on your outdoor cannabis lifecycle (or growth stages). Equatorial cannabis growers have 12/12 light (or thereabouts) almost all year round. This means you won't have any veg time at all if you grow outdoors.

Understanding the cannabis growth stages is key

With an increased understanding of the different cannabis growth stages you will find your control and enjoyment of cannabis cultivation will increase. As well as optimising your grow environment and improving your understanding of the cannabis grow cycle be sure to select the best cannabis seeds for your personal grow situation. The choice of cannabis seeds may seem large and possibly confusing.

If so please check out the Dutch Passion Seed Finder which asks a few simple questions before recommending the seeds which best fit your needs.